How to create an app with android studio


Create a simple calculator which can perform basic arithmetic operations like addition, subtraction, multiplication, or division depending upon the user input. A sample video is given below to get an idea about what we are going to do in this article. Note that we are going to implement this project using the Java language.

Step by Step Implementation

Step 1: Create a New Project

To create a new project in Android Studio please refer to How to Create/Start a New Project in Android Studio. Note that select Java as the programming language.

Step 2: Working with the activity_main.xml file

Navigate to the app > res > layout > activity_main.xml and add the below code to that file. Below is the code for the activity_main.xml file.

After using this code the UI will be like as follows:

How to create an app with android studio

Step 3: Working with the file

Open the file there within the class, and make a method named doSum(View v). In this method, first of all, we have to link two EditText with variables so that we can use them for our input. So link those edit box with variables we have written

Here num1 is id for the textbox and we are just giving a variable name ‘e1’ to text box with id ‘num1’. Similarly, we have to use the same statement for the second textbox with the variable name ‘e2’. For the third text box, we have used

Here we have used TextView because we only have to display text avoiding it being user-changeable. Now we have to input numbers in form of string using the getText() function. The input statement will be

Here s11 stores the number entered in textbox 1. We have to do the same with another Textbox(e2). Now store the number in int form and apply addition. store the added value in another variable. To display stored in sum we have to use setText() as follows:

I downloaded the Android studio and installed it. When I launched it, it’s all “graphical”. My screen reader is reading nothing on it.

I’d prefer if I could use my Notepad app, but the “stand alone” tutorials are too tiresome, and not many tutorials on the web have instructions making apps using Notepad. I wanted to know if there is an alternate IDE, or another way to code Android apps?

The Java IDE Eclipse is also not very compatible with my screen reader. I use JAWS screen reader by Freedom Scientific. I used to code Java desktop software using my Notepad, so I’m familiar with programming using Notepad.

Also, if I somehow figure out how to make Android apps using Notepad, how am I going to test them? Do I need a phone? I’m sorry for all these beginner questions, but I’m a beginner 🙂

How to create an app with android studio

3 Answers 3

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You can follow this link: If you only want to build, not run, you don’t need a phone. If you want test without a phone you can use an emulator by running”AVD Manager.exe” in Android SDK folder.

How to create an app with android studio

I wrote two small scripts for Android development without using Android Studio. They are building apk and installing it on the connected device and opening the logcat with the output of the installed application. This two scripts not even near to complete when to think all the features of the Android Studio but they are allowing to at least run the project on your phone.

The good thing since the transition to android studio is that now the building of an android project is done using Gradle and can be piloted entirely by command line. So technically, you don’t need an IDE at all.

Basically, every project has at least a build.gradle file that contains the instructions to build it. You only have to launch Gradle with the appropriate command to compile your app.

Yelliver mentionned the tools to build the app from the command line, there are also tools to create the project structure and the basic build files: (this documentation appears not to be entirely up-to-date, though, as it mentions the old format)

Having a phone to run your app is certainly going to be nicer and faster to develop. The emulator is far from perfect, quite slow, and sometimes not responsive. It is also easier to install other apps on your phone than on the emulator, in case your app interacts with other apps.

How to create an app with android studio

ok, this is my first article in Medium. In this section, I want to share with you about the User Interface on Android and we will create a Login page and a Register page. Some components that I will use:
1. Viewpager
2. Fragment
3. Edittext
4. Button
5. Textview
6. Imageview

What about the results? let’s coding (follow step by step)

  1. Of course we must already have an Android Studio. if not, you can download it first on the official Android Studio website. If you already have one, please open your Android studio.

2. We create a new project by clicking “Start a new Android Studio project”. Fill in the application name column with “LoginApp”, then click next.

How to create an app with android studio

3. Select the minimum SDK you need or want, then click next.

How to create an app with android studio

How to create an app with android studio

4. Select “Empty Activity” and click next. After that, the “Activity Name” and “Layout Name” columns will appear, in this section just leave it like that, then click finish.

How to create an app with android studio

After you click finish, Android Studio will make you an Application with the name “LoginApp”.

After the application is successfully built, you can simply make adjustments to the following sections:

Open the colors.xml file in app/res/values/colors.xml, and change it like this:

Create a folder with the name “font” in the res folder, by right clicking on the res directory, select new / directory and name it “font”. After that, copy this font into font directory. (download the font 1 and font 2).

Create some Drawable Resource File in the drawable directory, by right-clicking on the drawable directory, select new / Drawable Resource File.

After that open file styles.xml and change like this :

Add the theme property in the Main Activity in the manifest, in the app / manifests / AndroidManifest.xml folder

So the AndroidManifest.xml file will be as follows:

After all the steps above are done, then make 2 fragments with the name fragment_login and fragment_register in the layout directory, by right-clicking on the layout directory, New/Fragment/Fragment (Blank)

How to create an app with android studio

include fragment factory methods? and include interface methods?

How to create an app with android studio

change the activity_main.xml layout, fragment_login.xml and fragment_register.xml so that it will be as below

Open the strings.xml file in the res / values / strings.xml directory and change it to something like the following :

So that the overall structure of the project will be as follows :

How to create an app with android studio

Create an inner class in the class with the name AuthenticationPapterAdapter. This class is a derivative of the FragmentPagerAdapter class and serves to connect Fragments with ViewPager,

Then call the class in the onCreate() method in and connect with viewpager

So the class will be like this

The display of the final application will be like this

How to create an app with android studio

How to create an app with android studio

After the steps are complete please try running it on your device. for the full code, see my github or click here.

Maybe that’s just for the article about “ How to Create a Login User Interface & Register with Android Studio”, I hope to help your needs.

Here, we are going to make an application for the “GeeksForGeeks” website. By making this application we will be able to learn that how we can convert a website to an Android Application just by following simple steps. You can use this concept for your personal website too and learn something new.

How to create an app with android studio

What we are going to build in this article?

In this application, we will learn that how we can use different portals of a website and show them as fragments in our android application. In this application three portals of Geeksforgeeks website- Home, Practice and Contribute will be used as fragments in our application. So, that you can see a live example to convert a website to an application. The concept of WebView is used to do this desired work. A sample video is given below to get an idea about what we are going to do in this article. Note that we are going to implement this project using the Java language.

Simple Steps to Convert Your Website into an Android Application:

  • To add the logo of your application.
  • To add a splash screen to your application.
  • To use Navigation drawer in our application so that, different portals of our website can be used as fragments in the navigation drawer.
  • To use a WebView so that, the web content can be accessed easily.
  • To use WebViewController class so that the content on the Website can be directly shown in the application rather than opening it in the browser.
  • To add a helpline activity.

And by following these steps you can convert your website to an application in the simplest way. So, let us see step-by-step implementation to convert GeeksForGeeks Website to an application.

Step by Step Implementation

Step 1: Creating a new project

  • Open a new project.
  • We will be working on Navigation Drawer Activity with language as Java. Leave all other options unchanged.
  • You can change the name of the project at your convenience.
  • There will be many default files.

If you don’t know how to create a new project in Android Studio then you can refer to How to Create/Start a New Project in Android Studio?

Step 2: To add a logo to our application

  • Paste the logo of your application in res > drawable.
  • Follow “How to change the default icon of Android App” for further steps.

Step 3: To add Splash Screen to our application

Follow-“Creating a Splash Screen” to learn how to add a splash screen to our application. Sample design of splash screen of our application.

Step 4: Working with xml files

I’m using an android device. When I open the Settings > Apps > Running , there is an option on the top-left of the screen to see : (1) Running processes (2) Cached background processes. And the app(s) which I wanted to run always (24×7) is/are unfortunately listed under (2) Cached background processes, which I wanted it/them to be listed under (1) Running processes (if it is possible). Can it be done? Or in short, how to make an android app always run in the background?

I hope I conveyed the question 🙂

How to create an app with android studio

3 Answers 3

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You have to start a service in your Application class to run it always. If you do that, your service will be always running. Even though user terminates your app from task manager or force stop your app, it will start running again.

Create a service:

Create an Application class and start your service:

Add “name” attribute into the “application” tag of your AndroidManifest.xml

Also, don’t forget to add your service in the “application” tag of your AndroidManifest.xml

And also this permission request in the “manifest” tag (if API level 28 or higher):


After Android Oreo, Google introduced some background limitations. Therefore, this solution above won’t work probably. When a user kills your app from task manager, Android System will kill your service as well. If you want to run a service which is always alive in the background. You have to run a foreground service with showing an ongoing notification. So, edit your service like below.

How to create an app with android studio

Remember when phones were just phones? While you might use your Android device for pretty much anything but sending and receiving text messages most of the time (even to the point of preferring WhatsApp and other tools for written communication); SMS is still technically one of your phone’s primary uses at heart. And with that in mind, this is still a fundamental skill for us to learn as developers.

In this two-part tutorial, we will look at how you can go about creating a basic app that will send and receive SMS content, as well as how to retrieve messages from the inbox and navigate Android’s new permissions system. In part two we’ll explore how to work with background services and categorize our messages…

Note: You can get the full source code from GitHub here and I highly recommend looking through it as you read. This is a slightly more complicated project and so it will help to have it there in front of you while you read.

Like the last tutorial (how to build an image gallery app), I will be jumping into this assuming that you have a basic familiarity with Android Studio and Java. If that is not the case, then I invite you to check out this post on getting started with Android development and this post on creating a very basic Android app. And also check out Gary’s Java tutorial here. With that out of the way, let’s get down to business!

What is the simplest change that I can make to a new Blank Activity, as created by the latest version of Android Studio, to get the app to appear fullscreen?

I want to create a fullscreen Android application. I’m working with Android Studio. This post suggests that I add a line such as .

. to the AndroidManifest.xml file, as shown below:

When I do this, the app compiles but it crashes on launch. If I remove the line, the app runs fine, but with the action bar and a title bar, as also noted by other users.

This is my first attempt at creating an Android app, so my app is hardly altered from the original Hello World example.

EDIT: I created a new project, and made just this one change to it. Here is an extract from the error log:

NOTE: I am testing on a old Samsung SGH-T499Y, running Android 2.2 (Froyo)

How to create an app with android studio

16 Answers 16

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You are getting this problem because the activity you are trying to apply the android:theme=”@android:style/Theme.Holo.Light.NoActionBar.Fullscreen”> to is extending ActionBarActivity which requires the AppCompat theme to be applied.

Extend your activity from Activity rather than from ActionBarActivity

You might have to change your Java class accordingly little bit.

If you want to remove status bar too then use this before setContentView(layout) in onCreateView method

How to create an app with android studio

Just add the following attribute to your current theme:

How to create an app with android studio

just do this in your manifest file in your activity tag

in my case all works fine. See in logcat. Maybe logcat show something that can help you to resolve your problem

Anyway you can try do it programmatically:

How to create an app with android studio

Update Answer I added android:windowIsTranslucent in case you have white screen in start of activity

just create new Style in values/styles.xml

from your AndroidManifest.xml add style to your activity

to be like this

Simply declare in styles.xml

Then use in menifest.xml

How to create an app with android studio

In onCreate call

How to create an app with android studio

You can use the following codes to have a full page in android

Step 1 : Make theme in styles.xml section

Step 2 : Add theme on AndroidManifest.xml

Step 3 : Java codes section

For example you can added following codes in to the onCreate() method.

How to create an app with android studio

According to this document, add the following code to onCreate

If you Checkout the current Android Studio. You could create a New Activity with the Full-screen template. If you Create such an Activity. You could look into the basic code that Android Studio uses to switch between full-screen and normal mode.

How to create an app with android studio

This is the code I found in there. With some minor tweaks I’m sure you’ll get what you need.

Now I went further to checkout how this could be done in a more simple fashion. Making changes to the AppTheme style in your styles.xml file would be most helpful. This changes all your activities to a Full Screen view.

If you want only some activities to look Full Screen, you could create a new AppTheme that extends your current app theme and include the above code in that new style that you created. This way, you just have to set style=yournewapptheme in the manifest of whichever activity you want to go Full Screen

This example demonstrates how do I use the SQLite database with an android application.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

Step 3 − Create a new Java class (DataBaseManager) and add the following code −

Step 4 − Create a new Java class (DataBaseHelper) and add the following code

Step 5 − Add the following code to src/

Step 6 − Create Two Activities (AddPlayerActivity & ModifyPlayerActivity) and add the following code − −

activity_addplayer.xml −

ModifyPlayerActivity −

activity_modify_player.xml −

Step 7 − Create a layout resource file (action_view_record.xml) and add the following code −

Step 8 − Add the following code to androidManifest.xml

Let’s try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from the android studio, open one of your project’s activity files and click Run How to create an app with android studioicon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

Android application developers need a platform where they can test and debug their application. This platform can be in the form of a physical Android device or an Android emulator.

Android Studio provides a built-in default emulator for testing and debugging purposes.


Install Android Studio 3.0+

Android Debug Bridge ( adb )

Setting up the emulator

1. Installing Build-Tools

Open Android Studio and navigate to Preferences -> Appearance & Behavior -> System Settings -> Android SDK. Click on the SDK Tools tab and install one version of the Android SDK Build-Tools, if necessary.

2. Set configuration path

Linux or macOS users need to add the Android SDK Location path (see the image above) to PATH by appending the following line in

macOS users need to additionally add platform-tools to

./bash_profile . This can be done by adding the following line:

3. Configuring Virtual Emulator

Navigate to Configure -> AVD Manager in the Android Studio. Click on the Create Virtual Device option and select the relevant device emulator and the OS version to be installed on that emulator. Tweak the settings as required before clicking Finish. The virtual emulator will be created and can be used anytime by clicking on the play icon in the AVD Manager Window.

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How to create an app with android studio

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How to create an app with android studio

I just started Android Development a few days ago and noticed that doing some of the trivial things is also very challenging and non-intuitive in Android Studio.

Take the example of setting a background to an Activity.

If you want your UI(user interface) to be attractive then you have to set an attractive wallpaper or image as the background.

You can change the background in Android Studio in two ways:

    First way gets the job done easily but is not the best way to do it as I will tell later.
    All you need to do is add the following code to you activity’s layout xml file:

where background is the name of the image that you want to use as the background and is stored inside the drawable folder of your app.

The following images will help you understand the process better:
1. Take the image that you want to use as a background and paste it inside the drawable folder of your app

How to create an app with android studio Location of the drawable folder where ‘Test2’ is the name of the app

2. Go to the xml layout file of your activity and the following code to the parent layout:

where background is the name of the image that you want to use as the background and is stored inside the drawable folder of your app.
How to create an app with android studio

3.Background is changed!! 🙂
How to create an app with android studio

Note(Tip): Location of the xml files of layouts:
How to create an app with android studio

Though the above method seems pretty good, it is pretty flawed.
Therefore, we look at a better way to change backgrounds, which takes us to method #2.
Method #2:
Using ImageView.
A background can be set for an activity by using an ImageView pretty easily.
1. Create an ImageView inside your activity’s layout.2. Set

4. and just set the

where ‘background’ is the name of the image you want to be used as background and is stored inside the drawables folder of your app.So that your ImageView looks like this:
How to create an app with android studio
Now, let’s come back to why I recommend/prefer the second method rather than the first.

The first reason is that if the background image that you are using does not have the same aspect ratio as the device it is being run on, then the image gets stretched or compressed and spoils the look of the background.

However, with ImageView we can use the

which crops the image according to the device’s resolution and maintains the aspect ratio.

Have a look at how the background looks with both the methods:
Using Method #1: ‘android:background=….’

How to create an app with android studio background gets stretched and compressed in portrait mode How to create an app with android studio background goes out of aspect ratio and gets a little stretched and compressed to fill the screen

Using Method#2(ImageView):

How to create an app with android studio The Background image gets cropped to maintain the aspect ratio in portrait mode How to create an app with android studio The Background image gets cropped to maintain the aspect ratio in landscape mode

Moreover, another advantage of ImageView is that we can set the alpha value for the background.
Alpha value is a number between 0-1, which decides the transparency/opacity of the background, 1 being fully visible and 0 being fully transparent..

So if you think that your text is the same color as the background and is not very clear then you can set a small value for alpha like 0.28.

That’s it. I hope that helped.
If you have any questions or doubts drop them in the comments section below.

Watch the following video for the video version of the above tutorial.

Last Updated on August 20th, 2017 by Kuldeep 20 comments

How to create an app with android studio

In my previous article I wrote detailed steps on How to create a simple android application. In that particular app I also explained concepts of android button and basic concepts of android.

You can find all my other articles in Android section.

In this article we will create a calculator android app . This is a simple calculator with limited functionality.

Before we go forward it would be nice to go over complete HelloWorld Tutorial. Here is a link again: My first HelloWorld Android App

  • How to build a simple calculator app – full tutorial
  • Building a Simple Calculator using Android Studio
  • Android Development: Creating a Basic Calculator
  • Create Simple Calculator Android App
  • How to create a Calculator App for Android

Let’s get started with our calculator android App:


  • Open your Android Studio
  • Click on Start a New Android Studio Project.
  • Give your Application Name CrunchifyCalculator and leave other fields blank as it is, then click NEXT.

How to create an app with android studio


  • Select the Minimum SDK API 15: Android 4.0.3(IceCreamSandwich) . I selected API 15 (IceCreamSandwich) because it covers almost 94% device and it has almost all the features. If you want to cover 100% device then you can select API 8: Android 2.2(Froyo).

How to create an app with android studio


  • Select the Empty Activity and click NEXT.
  • Leave the activity name MainActivity as it is and leave everything as it is. Click Finish.

How to create an app with android studio


  • After clicking Finish, it takes around around

2 minutes to build Activity and files.

  • Here is a final project structure for your application.
  • How to create an app with android studio


    • Now we have to add our Java code in our file.
    • So open you file from left side of IDE (app -> java -> com.crunchify.tutorials.crunchifycalculator ->

    You can find the explanation of highlighted line below the code.

    Here we have 1 EditText. It defines the type of content.

    Let’s understand code little-bit more.

    • Line 11 – 14: Here we created the reference of Buttons and EditText.
    • Line 16: Here we created two float variable for as value1 and value2.
    • Line 21: We override the method onCreate() which is the method of Activity class.
    • Line 45 – 50: We set onClickListener on Button1. If we click on Button1, EditText will display.
    • We have implemented the same logic for every button.
    • Line 115 – 127: Here we have set the click listener on Add button.
    • Here we put the condition as, if we EditText is Null then we set EditText as empty value. Else we add the two value which are clicked before add button clicked and after add button clicked.
    • We also set the crunchifyAddition Boolean value to True. This true represent that add button is clicked and this will be used when user click “=” button.
    • We implement the same logic for other buttons also like buttonSub, ButtonMul, buttonDivision.
    • Line 156 – 183: Here we set clickListener on “=” button. Here we put condition like if user click Add button the crunchifyAddition value is set True on the click listener of Add button.
    • According to that, corresponding action will be performed respective to button clicked.
    • After the action performed, we set the crunchifyAddition value to false, so that we can perform Add action again.

    Below is the layout file, with help to design front end for the calculator:

    Document scanner apps are one of the more popular tools that make smart use of mobile device features, like the built-in camera and touch-screen, to make scanning both convenient and practical for virtually anyone.

    For example: Google Drive’s document scanning feature lets you take pictures of items such as receipts, letters, billing statements, etc. and save them as PDFs on your Drive. But the resulting PDF document only contains static images without any interactive text.

    In this post, we recreate this feature and take it a step further, teaching you how to create a document scanner app for Android using PDFTron’s OCR module. This makes text in your scanned documents searchable and selectable. And since we’re using PDFTron to view the resulting PDF file, we can also annotate and edit the document!

    Sample code for this post and an Android document scanner example can be found on Github, and you can try our sample by installing the APK here.

    To keep things simple, the OCR portion uses Google’s ML Kit Text Recognition APIs, while the client scanner app is based on our fork of a third-party Android document scanner library, AndroidScannerDemo.

    Client Setup for Android Document Scanner with PDFTron SDK

    Create a new Android project using Android Studio.

    Add Google’s ML Kit Text Recognition Android libraries as described in the ML Kit guide.

    Download the following AAR file and add the AAR as a new module dependency in your project.

    Integrate the PDFTron library via Gradle, as described here.

    Next, as mentioned previously, the Android app will use our fork of a third-party Android document scanner library, found here. We’ll use this library to capture, crop, and filter images using the built-in camera.

    You can launch the scanner and handle the returned image by calling the following in your MainActivity. (Note: The processOCR method will be implemented later in the guide.)

    Now let’s add code that will help us with the OCR portion, which creates searchable and selectable text from static images. There are two steps: process the image using ML Kit, and then create a PDF using the scanned image and processed text.

    In your MainActivity, add the following methods:

    Now you can capture a physical document, upload it to ML Kit for text recognition, and open the text-searchable and -selectable PDF document in the PDFTron viewer.

    How to create an app with android studio

    More Features, Next Steps

    By following the steps above, you’ve created a professional Android scanner app for your invoices, bills, letters, and other paper statements. And by using the PDFTron document viewer, you can then mark up those scanned documents by adding annotations, signatures, stamps, and much more! You can also drop in loads of other PDFTron SDK capabilities if you wish, such as redaction, page manipulation, etc. to edit your scanned documents.

    Download our free trial and explore our guides & documentation for our Android PDF library to see the possibilities for yourself.

    And if you have any questions, please feel free to get in touch !

    You can find the source code for this blog post at Github.

    How to create an app with android studio

    • Menu bar for style, edit, format and view
    • Edit text with copy function with toast.
    • Format texts with changing the font size.
    • To create a new document.txt file.

    Step 2:
    First we want to create a notepoint layout. Add 6 buttons for operations (like : bold, italic, normal, copy and more). Add 1 MultiAutoCompleteTextView Or EditText.

    For each operation, we created a ActionListner and give the appropriate for each.

    Step 3:
    In this code you get following :
    1. How to change the text color in android studio.
    2. How to change the text font size in android studio.
    3. How to show the message in Toast.
    4. How to create contextmenu in android studio and more.
    Step 4:
    How to change line color in ( EditText and MultiAutoCompleteTextView ).
    Add one xml file in you project. Give any name what you want.

    That’s it! Download the files. Thanks for reading!

    If you have any doubt regarding the creation of android app then leave your doubts in the comment box.

    In this tutorial, we will create a Weather Forecasting application in android using java. We can create an android project either using Android Studio or Eclipse IDE. For using Eclipse IDE we need to add ADT plugin, SDK manager, and Android Version. Therefore we can say that using Eclipse IDE is a lengthy process so instead of using Eclipse IDE most of the developers prefer using Android studio. We can use any version of Android Studio.

    In this project, we are using Android Studio 3.6.3.

    Create Weather Forecasting app in Android Studio

    1. Open Android Studio and click on the file option on the upper left corner of the screen.
    2. Click on the new option and select the wizard that you want and click on the next option.
    3. Now enter the details that are the name of the project, name of the package, and android version.
    4. Click on the finish option. (You will get two files and activity_main.xml)
    5. In the write java code and in activity_main.xml file write code to design front-end of the app.

    VIEW of the screen:

    How to create an app with android studio

    To design the front-end of the application we write code in activity_main.xml and for providing functionality to our application we write java code in file. We can even create more classes in the same package.

    In the above code com.example.weatherforecasting1313 is the name of our package. Further, we are importing all the required classes and interfaces. But we don’t need to worry about these classes as we can directly import these files by pressing “Alt+Enter” after writing the method from that class that we need to import. Further, we created the variables of String, EditText, and TextView. In the onCreate method of our class, we set the visibilities of several text views as per our requirement. View.VISIBLE means that the TextView is visible on the front view and View.GONE means that the TextView is not visible on the front end of our application.

    Further, we created the doInBackground method in which we are passing the

    String response = HttpRequest.excuteGet(“”+CITY1+”&units=metric&appid=73cbebdd0322acd49bda6ede059b2b18”);

    Here 73cbebdd0322acd49bda6ede059b2b18 is the key of the API used.

    create your account

    after creating account Log-In here to get the API

    HttpRequest is the name of our class in the same package which we are using to fetch data.

    JSONObject is the constructor used to convert external form JSON (Javascript Object Notation) text into an internal form which we can retrieve with getRequest and can convert values into JSON text using the toString method.

    The SimpleDateFormat is used to set the format of the data which we want to display on the TextView to be viewed on front end of our application.

    Again we are setting data to the TextViews and setting the visibility of the TextViews used.

    First of all, we created the parameterized method executeGet in which targetUrl is the URL we passed in our MainActivity class in response variable in which we passed our API key. Then we opened the link and set our RequestMethod as “GET” as we want to fetch data. Further, we are writing our code in the try-catch block so as to handle Exceptions. The finally block is always executed whether an exception occurs or not.

    Buffered Reader is class that is used to read text from character input stream buffering characters so as to read characters efficiently.

    The method getResponseCode is used to retrieve the response status from the server.

    In finally block we are disconnecting the connection as finally block is always executed whether Exception occurs or not.

    For designing the front end of our application we can use two methods.

    1. We can directly drag and drop the required fields.
    2. We can write the XML code for the required code.

    If we will drag the required field our XML code will be generated automatically.

    While designing the front end we just need to specify the layout and id of the field rest all are generally for the design purpose. In the textColor option “#000000” is the hashcode for the black color.

    Setting the layout is also important as layout determines the view of our front-end.

    We can add as many attributes as we want. But in this tutorial, I only added the basic and required attributes.

    To add images as background we need to download the image and save it in the drawable folder.


    First of all, we will get the EditText with hint Enter City.

    How to create an app with android studio

    Then we will enter the name of the city and click the button Search Temperature.

    How to create an app with android studio

    After clicking the button we will get the screen showing the required data.

    How to create an app with android studio

    4 responses to “Weather Forecasting Android App using OpenWeatherMap API in Android Studio”

    The app is crashing on clicking the button and api key had expired but i got a new one but kindly fix the error in the app or guide me how to make the app work

    Hey, I also got that problem and i found the solution, so first you gotta insert this: , in the manifest file so it can access the internet, and second the URL might be wrong, i can’t post here because it’s considered spam but if you head to the openWeather site and get the right link, it will work.
    Hope this helps.

    Forgot the permission which is this:

    the application is not running in the device (installing in the device but can’t able to able to open

    Like many, I know nothing about Java. Oh wait a minute, Java and C++ have similar syntax and I did learn the latter. But still, I have no clue about how to create an Android app, not to mention Android spy apps.

    But this should not be an obstacle. I recently get to know that someone has already released the source code for an Android Remote Access Tool (RAT) known as AndroRAT. It allows you to remotely control any Android device which installs this app, read its messages, phone book, call log, use its camera and microphone, and pinpoint it on a map in real-time. Basically you can do anything you want, free of charge. In fact, there are already many AndroRAT based Android spy-ware out there.

    Here I will introduce how to customize it and get the app working the easy way.

    In order to begin the whole process, you will need to get a few things ready. If you alrady know a lot about Android and Android apps, then it should be a piece of cake. Even if you are completely new to Android, it’s still quite easy as long as you know how to install software on your computer.

    There are actually three software need to be installed, eclipse (Eclipse IDE for Java Developers), Java Platform, and Android SDK.

    Once you are done with the software installation, head over to github and download the Androrat files, what really matters is the source code folder names src. The Androrat sub-folder is for the Android phone, and AndroratServer is for the server side. But first, you need to customize and compile them.

    Now open eclipse and import Androrat, you will see two projects.

    How to create an app with android studio

    Now import two jar packages. If other packages are missing, you can always download them at FindJar.

    How to create an app with android studio

    I tried to run them directly. First the Server app, see below. The settings like server port can be changed via config.txt or the source code. In fact, you can change the IP address there too. If you have a domain name, better replace the IP address with it.

    How to create an app with android studio

    Then the mobile app (I did not compile it here), it will switch to the home screen automatically once you are done with installation, and you won’t find it in recent apps. It names itself LogsProvider, but you can change it to whatever you wish. Better something like a normal app so others won’t have any doubts.

    How to create an app with android studio

    In order to better hide and protect the app, there are a few changes to be made in LauncherActivity.class.

    How to create an app with android studio

    A few possible tweaks below, although you may not see the same gui.

    How to create an app with android studio

    Note, in order to run it on other devices the easy way, you need to compile the mobile files and create an apk file.

    i, build a PHP based server side script which will handle the data transferred from the mobile app and save them in MySQL. You can later display these data on a webpage and a map. You can even let others create an account and let many people use this service, paid or for free.
    ii, create a service and monitoring SMS, connect to the server once text message contains certain keywords arrive.
    iii, hide from anti-virus apps or even kill them.

    This guide will help you to get started using Xamarin.Android on Windows to create a cross-platform app that will work on Android devices.

    In this article, you will create a simple Android app using Xamarin.Android and Visual Studio 2019.


    To use this tutorial, you’ll need the following:

    • Windows 11 or Windows 10
    • Visual Studio 2019: Community, Professional, or Enterprise (see note)
    • The “Mobile development with .NET” workload for Visual Studio 2019

    This guide works with Visual Studio 2022, Visual Studio 2019, and Visual Studio 2017. If you’re using Visual Studio 2017, some instructions might be incorrect due to UI differences between versions of Visual Studio.

    You will also need to have an Android phone or configured emulator in which to run your app. See Configuring an Android emulator.

    Create a new Xamarin.Android project

    Start Visual Studio. Select File > New > Project to create a new project.

    In the new project dialog, select the Android App (Xamarin) template and click Next.

    Name the project TimeChangerAndroid and click Create.

    In the New Cross Platform App dialog, select Blank App. In the Minimum Android Version, select Android 5.0 (Lollipop). Click OK.

    Xamarin will create a new solution with a single project named TimeChangerAndroid.

    Create a UI with Android XML

    In the Resources\layout directory of your project, open activity_main.xml. The XML in this file defines the first screen a user will see when opening TimeChanger.

    TimeChanger’s UI is simple. It displays the current time and has buttons to adjust the time in increments of one hour. It uses a vertical LinearLayout to align the time above the buttons and a horizontal LinearLayout to arrange the buttons side-by-side. The content is centered in the screen by setting android:gravity attribute to center in the vertical LinearLayout .

    Replace the contents of activity_main.xml with the following code.

    At this point you can run TimeChangerAndroid and see the UI you’ve created. In the next section, you will add functionality to your UI displaying the current time and enabling the buttons to perform an action.

    Add logic code with C#

    Open MainActivity.cs. This file contains the code-behind logic that will add functionality to the UI.

    Set the current time

    First, get a reference to the TextView that will display the time. Use FindViewById to search all UI elements for the one with the correct android:id (which was set to “@+id/timeDisplay” in the xml from the previous step). This is the TextView that will display the current time.

    UI controls must be updated on the UI thread. Changes made from another thread may not properly update the control as it displays on the screen. Because there is no guarantee this code will always be running on the UI thread, use the RunOnUiThread method to make sure any updates display correctly. Here is the complete UpdateTimeLabel method.

    Update the current time once every second

    At this point, the current time will be accurate for, at most, one second after TimeChangerAndroid is launched. The label must be periodically updated to keep the time accurate. A Timer object will periodically call a callback method that updates the label with the current time.

    Add HourOffset

    The up and down buttons adjust the time in increments of one hour. Add an HourOffset property to track the current adjustment.

    Now update the UpdateTimeLabel method to be aware of the HourOffset property.

    Create the button Click event handlers

    All the up and down buttons need to do is increment or decrement the HourOffset property and call UpdateTimeLabel.

    Wire up the up and down buttons to their corresponding event handlers

    To associate the buttons with their corresponding event handlers, first use FindViewById to find the buttons by their ids. Once you have a reference to the button object, you can add an event handler to its Click event.

    Completed MainActivity.cs file

    When you’re finished, MainActivity.cs should look like this:

    Run your app

    To run the app, press F5 or click Debug > Start Debugging. Depending on how your debugger is configured, your app will launch on a device or in an emulator.

    System requirements

    To install and run Flutter, your development environment must meet these minimum requirements:
    Operating System: Windows 7 SP1 or later (64-bit)
    Disk Space: 400 Mb (Except disk space of IDE/tools)
    Tools: Flutter depends on these tools being available in your environment.
    Windows PowerShell
    Git for Windows

    Get the Flutter SDK

    Step 1- Go to URL and download the latest Flutter SDK.
    Step 2- Unzip the zip file and place the contained flutter in the installation location for the Flutter SDK (For example, C:/src/flutter; do not install FLutter in a directory like C:/Program Files/ that requires relevant privileges).
    Step 3- Update your path
    From the Start search bar, enter ‘env’ and select “Edit environment variables for your account”.
    Under User variable check an entry called Path.
    Under Path click on the new tab and append the full path to flutter/bin. (Your full path should be like C:/src/flutter/bin).

    Android Setup

    Install Android Studio

    Download and install Android Studio.
    Start Android Studio, and go through the ‘Android Studio Setup Wizard’. This installs the latest Android SDK, Android SDK Command-line Tools, and Android SDK Build-Tools, which are required by Flutter when developing for Android.

    Install the Flutter and Dart plugins

    Open Android Studio.
    Click Configure>Plugins.
    Select the Fluter plugin and click install.
    Click yes when prompted to install the Dart plugin.
    Restart Android Studio.

    In this article, I am going to show you how to create an android APP from angular using Angular 8 or Angular 2+ using Cordova.

    first, create an angular app

    then your project look like this

    How to create an app with android studio

    now run the app

    now check http://localhost:4200/ if everything is fine then in your browser it will look like this

    How to create an app with android studio

    install Cordova plugin using npm

    create new Cordova project

    How to create an app with android studio

    then Cordova project look like above

    copy all the folders and files except package.json from the Cordova project to your angular project. result folder structure photo will look like below

    How to create an app with android studio

    merge Cordova project package.json to angular project package.json. the resulting package.json file looks like below

    How to create an app with android studio

    now in angular.json change “outputPath”: “dist/android-tutorial” to “outputPath”: “www”, because Cordova need build here

    in angular project move or copy from www/index.html content to src/index.html. now your src/index.html look like this and change

    How to create an app with android studio

    Add android or ios plugin to your Cordova project

    Generate production build

    How to create an app with android studio

    www/index.html file looks like this and copy the js/index.js folder from cordava/www project to angular www/

    How to create an app with android studio

    and do not forget add type=”text/javascript” to all script tag other wise you will get file:/// null cros errorsomething

    Let us build android apk from www folder content, to do so run the below command and make sure you installed android studio and set JAVA path to 1.8 version and ANDROID_HOME to SDK and path to tools and platform-tool in your system env files

    android apk build path

    copy apk to your mobile. Final apk photo from mobile

    How to create an app with android studio

    How to create an app with android studio

    I showed you the simple steps to create an android app from angular which unsigned, to publish to the play store you have to generate the signed apk. and you can build an ios app using Cordova build ios. and I installed it on my mobile working fine. I have a big personal angular project that is successfully converted to android apk without any problem but I got some performance issues like back button not great in-app and very laggy in low ram mobiles, that’s it if you any doubts please let me know comment section.

    Step by step guide to building a barcode scanning application using Android Studio.

    This article will guide you through creating an android application using which you can make use of your mobile camera to scan a barcode and read the data in them.


    1. The latest version of Android Studio installed. ( download from here )
    2. A mobile device to test the application. (you can make use of the inbuild android emulator but in some pc, it may cause some issues.)
    3. Knowledge of java or any object-oriented programing language.

    Let’s write some code

    1. Create a new application in android studio and name it Barcode Scanner.
    2. Open up your app-level Gradle file and add the below dependency there.

    3. Now hit on Sync now button and wait for the build to complete. Once the build is complete open up your manifest file and add the necessary permissions.

    also, add the metadata field in your manifest file, inside the application tag and above the activity tag.

    here’s a full view of my manifest file

    4. Now you have set up all the dependency needed for the barcode scanner to work and all the permission necessary. Let’s build the UI for the app.

    5. Open your activity_main.xml file and write the below code inside.

    Now your view should look something like this

    How to create an app with android studio

    here we have something called a sufaceview in android and a textview field to display the text scanned by the barcode.

    SurfaceView: It provides a dedicated drawing surface embedded inside the view hierarchy.

    You have completed the UI code for the Barcode App, now let’s write the java code to make wonders happen.

    6. Open file and you will see the following code.

    let’s add some code of our own

    7. First, we need to bind the views.

    8. Now we will write the method to scan the image for a barcode.

    this method will help us scan and display the text in the textview we created in the XML file.

    9. The complete java code will look something like this.

    Now try scanning this barcode and you will see the value that is embedded in the barcode in the textview.

    How to create an app with android studio

    The final screen should something like this.

    In android, we can lunch other applications using packing name. This example demonstrate about How to Launch an application from another application on Android.

    Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

    Step 2 − Add the following code to res/layout/activity_main.xml.

    In the above code, we have created one textview. When you click on textview, it will open YouTube.

    Step 3 − Add the following code to src/

    In the above code, we have taken YouTube package name to open you tube application as shown below –

    Let’s try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from android studio, open one of your project’s activity files and click RunHow to create an app with android studioicon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

    How to create an app with android studio

    In the above result, it is showing default screen, when you click on text view. it will open YouTube as shown below –

    Learn to create your own currency converter as a means of learning the core concepts behind Android application development in Java.

    Join the DZone community and get the full member experience.

    I have been working on a number of projects as of late and today I wanted to share with you some of them.

    This tutorial will take you through a step-by-step process on how to create a simple currency converter app in Android studio.

    We shall be using Java and at the same time to convert this application to Kotlin (if time allows).

    Java and Kotlin are now the most popular Android development languages, with the latter being the official programming language for making apps in Android Studio.

    We assume all factors EW constant, you have Android Studio installed on your PC, and the environment has been properly set up.

    As such, in this tutorial, we are going to use Android Studio for our simple currency converter Android application.

    Simple Currency Converter Android App Example and How to Create It

    Open Android Studio from Start Menu > All Programs or simply tap the icon on the desktop to get started.

    How to create an app with android studio

    Wait for a few minutes as Android Studio launches. This may take a while depending on the computer speed processor or RAM. You may need to wait until Gradle Sync is finished.

    Once Android Studio has been fully launched, go to File > New and Create a new Project and name it Currency Converter App or anything you want.

    How to create an app with android studio

    Click Next, then select the Form Factors and minimum SDK. Just tick Phone and Tablet and select at least API 15: Android 4.0.3 (IceCreamSandwich). We are targeting this API because it powers at least 90% of all Android devices in the world.

    How to create an app with android studio

    You should always try to make Android applications compatible with the majority of the Android devices in the market.

    Click Next and Add an empty Activity to our Project.

    How to create an app with android studio

    In Create a new empty Activity, simply continue with defaults and click Finish.

    It’s now time we make our simple currency converter application. You’ll have to wait until Gradle Sync is finished to continue with the tutorial.

    So, in this case, we shall create two files (in fact, Android Studio has already created them for you) the and Activity_main.xml.

    We shall put all our Simple Currency Converter source code in activity_main.xml and the Java implementations in


    To create the interface below, you can simply copy and paste the source code below or follow some of these procedures to create this simple Currency Converter interface.

    How to create an app with android studio

    Go to res folder > Layout and select activity_main.xml. Click Text to add the following piece of XML code.

    Relative Layout

    In this tutorial, we shall use Relative Layout to align our currency converter app widgets. You can add Relative Layout to the activity_main.xml file by implementing the code snippet below.

    Plain Text (Text View)

    We need to add a Text View with the text “Enter Currency in dollars,” assuming we are doing a currency converter for converting dollars to euros.

    You can implement this by adding the following code below to activity_main.xml file.

    Edit Text View

    This widget will allow a user to add a figure or currency that needs to be converted. You can also implement the Edit Text widget in activity_main.xml using the code snippet below.

    Note: Text hint allows Edit Text widget to show sample information or give a hint; a user is required to add to this field or box.

    Button Widget

    You can now add the button widget that a user clicks and converts the figures in an Edit Text widget to another currency. Use the code snippet below to implement this.

    Note: The on Click Method, convertToEuro , will be used in our Java code.

    Image View

    To make our application look nice, you may need to add some image widgets with an image placed below the button. Use the code snippet below to add this piece of code to your Simple Currency Converter App.

    Note: You’ll have to download a sample image from Google. Copy and paste it in your drawable folder (drawable is also under res).

    After that, everything is complete for our activity_main.xml file. We shall have something like the code below.


    Add Java Code Implementations in the File

    Head back to Java > com.example.currencyconverterApp and select MainActivity.

    First, you’ll find the onCreate method already created for you in the Main Activity Java file. This is code snippet for the onCreate method.

    We now need to implement our very own convertToEuro method that we added to the button in activity_main.xml, as shown below.


    In the int euro = 2000; bit of code, 2000 is just a variable you can change to any currency rate depending on the Currency Converter App you want to make.

    The result/output will be displayed as a toast. You can as well show it on the Activity_main.xml interface as TextView by adding the code snippet below.

    Add this code implementation in the Java file, MainActivity.

    I hope this was helpful to all those who want to create a simple app in Android Studio. You can leave a comment in the section below if you any issues with the implementations.

    Published at DZone with permission of Martin Tumusiime . See the original article here.

    Opinions expressed by DZone contributors are their own.

    How to create an app with android studio

    Today in this tutorial, we’re going to see how to create a custom AppBar/ActionBar/ToolBar in android.

    I also already created a tutorial on this topic, but here I will demonstrate it with different examples.

    for circle image view:

    now go to your styles.xml file and set the theme to NoAction Bar so that we can create our own toolbar.

    now go to your main XML file and create a ToolBar and set the width and height, make sure min-height should be actionBar size.

    this will give you just a toolbar without any field. Look at the below image.

    How to create an app with android studio

    • Let’s add a Logo

    for the logo, we’re using a circular image view. Already add the dependency. Put it inside the toolbar and do the adjustment.

    here we set our title to null, so in the main java file assign our toolbar and do the below change

    the result will be:

    How to create an app with android studio

    we can also set the logo by using app:logo=”your logo here” in your toolbar

    the result will be:

    How to create an app with android studio

    • Now, add a title and a menu

    for the menu, create a menu android resource folder and create a menu resource file ( /res/menu/custom_menu.xml)

    import that menu in our main java file by using these code of lines

    for adding a title simply add a textView inside the toolbar.

    How to create an app with android studio

    Could you please checking for the Android support library?

    Open the SDK Manager form a toolbar of Android Studio and then the SDK Manager will appear. Scroll down to the Extra, make sure that “Android support library” and “Android support repository” are installed if not you have to install them and try to build the project again.

    How to create an app with android studio

    How to create an app with android studio

    How to create an app with android studioGeneral How to create an app with android studioNews How to create an app with android studioSuggestion How to create an app with android studioQuestion How to create an app with android studioBug How to create an app with android studioAnswer How to create an app with android studioJoke How to create an app with android studioPraise How to create an app with android studioRant How to create an app with android studioAdmin

    Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

    Implement automated release signing without uploading your KeyStore file to your repository

    How to create an app with android studio

    R eleasing an app to an app store like the Google Play Store is a common task that Android developers have to go through.

    Because you need to verify that you are the owner of the respective app, you need to digitally sign your APK ( Android application package) or AAB ( Android App Bundle) before being able to upload it.

    To be able to sign your application, you need to generate a .jks ( Java KeyStore) file that contains your certificate.

    If you are working alone on your app, you can easily use the Android Studio’s built-in Generate Signed Bundle/APK function.

    However, if you work in a team, in most cases you want everyone to be able to access the respective Keystore and credentials.

    Because sharing the credentials and KeyStore is a security issue, a common approach is to upload the KeyStore to version control and store the credentials in the respective secrets.

    While this might be an acceptable trade-off for private repositories, it can not be an option for a public repository. Even if your credentials are safely stored in the secrets, you don’t want everyone to be able to access your KeyStore file.

    The solution to this problem I want to share with you in this article is to encode the KeyStore file and also safely store it in your secrets, just like the credentials.

    We can then use a CI/CD ( Continuous Integration / Continous Delivery) to decode the secret on the flight back to a KeyStore file and safely sign and upload your release application.

    For example, I will show you how to create a GitHub Workflow to achieve that behavior.

    1. Gradle Set-Up
    2. Encoding The KeyStore
    3. The GitHub Workflow
    4. Conclusion

    Before we can start with the actual implementation, we need to set up signing-config in our app-level build.gradle to use environment variables from our GitHub secrets, which we will later set up.

    The following code snippet first takes our decoded KeyStore file from the temporary GitHub Workflow folder and copies it to our app folder.

    By using this approach we can locally leave the KeyStore file in the respective path, add it to the .gitignore, and keep being able to build our gradle file.

    The proceeding lines set environment variables to our release config.

    The next step treats the encoding of the KeyStore file. At this point, I assume you already own your KeyStore file. If you don’t have experience with app-signing, I suggest you take a look at the already mentioned documentation.

    For encoding, we will make use of the popular Base64 encoding scheme. Base64 doesn’t stand for specific but various encoding schemes that allow you to convert binary data into a text representation.

    In our case, the encoding of the KeyStorefile will allow us to store the file as text in our GitHub Secrets and later on in the GitHub Workflow process decode it back to our original KeyStore file.

    The encryption step can easily be done by using OpenSSL. Download and install it, then navigate to the folder that contains your .jks file. Within the respective folder, execute the following command in your Unix terminal or just use Git bash on Windows:

    If everything went right, you should see a newly created file your_signing_keystore_base64_encoded.txt which contains a cryptic text that represents your KeyStore file.

    To build our CI/CD pipeline, we will use GitHub Actions. But before we can start implementing our Workflow, we first need to set up our GitHub secrets.

    3.1 Set up your GitHub Secrets

    In the following section, I assume that you used the identifiers from the mentioned build.gradle file. If you renamed the environment variables, you need to adapt the GitHub Secret names accordingly.

    The first secret we will add is the encoded Base64 representation of our KeyStore file. To do so, go into your project’s GitHub secrets and add a new GitHub Secret called KEYSTORE.

    Copy the content from the your_signing_keystore_base64_encoded.txt file and paste it into the value field.

    Next, create a secret that is called SIGNING_STORE_PASSWORD and contains your KeyStore password.

    Afterward, create one that is called SIGNING_KEY_PASSWORD and contains your key alias password.

    The last secret we need to add is called SIGNING_KEY_ALIAS and should contain the alias of your app.

    3.2 The Workflow

    Now that we set up our secrets, we can proceed with the actual Workflow.

    Because we later want to be able to manually trigger our Workflow, we will define it as on: workflow_dispatch .

    To decode our encoded KeyStore file, we use the base64-to-file GitHub Action by Tim Heuer.

    With mobile apps becoming ever-present in users’ lives, following best security practices has become essential in protecting your users and your apps. Implementing security alone and from the ground up can be costly for your development team, create a less-than-ideal user experience, and be susceptible to design/implementation errors. The easiest path to strong security, and a positive user experience, is to turn to the experts.

    The Okta OIDC SDK can help with this in many ways: – Our security experts take the development effort of creating a secure authentication method off your plate – OAuth 2.0 and OpenID Connect allows your users to easily authenticate on your app with social login, using industry-standard secure protocols

    This post will show you a simple example of how you can use Okta OIDC SDK to create a (Kotlin) Android app with authentication.

    • (TLDR) Download the Finished App with Android Authentication
    • Create Your First Android App
    • Get Your Okta OIDC Configuration Settings
    • Add a Sign-in Button to Your Android App
    • Give Your Android App Permission to Use the Internet
    • Add Okta OIDC SDK to Your Android App
    • Configure Okta OIDC in Your Android App
    • Log in Using Okta OIDC
    • (Optional) Add Social login
    • (Optional) Biometric Login
    • Learn More About Android Auth and OIDC

    (TLDR) Download the Finished App with Android Authentication

    If you want to follow along using a completed version of the app, clone this repository from GitHub:

    Create Your First Android App

    First, you’ll need to download and install Android Studio. Next, launch the app and navigate to FileNew…​New Project…​. Then, create an “Empty Activity” for “Phone and Tablet”. You should now see a screen similar to this:

    How to create an app with android studio

    Choose a “Package name” related to a domain you own (I own, therefore I used com.akaita.myapplication in the example), a Save location you can remember, “Kotlin”, and a “Minimum API level” of 23 . Finally, click Finish.

    Get Your Okta OIDC Configuration Settings

    Before you begin, you’ll need a free Okta developer account. Install the Okta CLI and run okta register to sign up for a new account. If you already have an account, run okta login . Then, run okta apps create . Select the default app name, or change it as you see fit. Choose Native and press Enter.

    Use for the Redirect URI and set the Logout Redirect URI to (where is your Okta domain name). Your domain name is reversed to provide a unique scheme to open your app on a device.

    The Okta CLI will create an OIDC Native App in your Okta Org. It will add the redirect URIs you specified and grant access to the Everyone group. You will see output like the following when it’s finished:

    NOTE: You can also use the Okta Admin Console to create your app. See Create a Native App for more information.

    Add a Sign-in Button to Your Android App

    Now that you’ve finished up in Okta’s Admin Panel, head back to Android Studio and add a button to your res/layout/activity_main.xml . Replace the contents of this file with the XML below.

    This button will be used to authenticate using OAuth 2.0 + OpenID Connect, thanks to the Okta OIDC SDK.

    What will you learn

    1. Starting another activity using Intent

    Note: Find the full code of the project towards the end of the post. Read the entire post for further clarification and explanations.

    Before we get started, let’s take a look at the working application to see what you are going to build.

    How to create an app with android studioAn example of an intent to start a new activity

    Building the Interfaces

    This is our first application, in which we require two activities. We will use the intent function to go from one activity to another.

    How to create an app with android studio

    Start your project with an Empty Activity.

    The interface of the first activity

    All we need in our first activity is a button, which, when pressed, will take us to the next activity. By default, we have the ConstraintLayout set. As we aren’t dealing with a lot of items, we will let it be like this.

    1. Drag and drop a button under the default ‘Hello World’ text.
    2. Set the ID of the button to something you will remember.
    3. Give the button a function name in the onClick option from the properties that you will remember.
    4. You can add constraints to this button, if you don’t remember how to do that, then I highly recommend you go through this article that will help you recollect your memory.

    You can find the code to the interface of the activity at the bottom of the article.

    Adding a new activity to the project

    Next, we need to create the activity ( the screen ) where the button will take us. We can do this in many ways. The easiest one goes like this.

    Another really easy way of doing this is from your project sidebar.

    The default settings will name this activity as ‘Main2Activity’.

    Adding the new activity in AndroidManifests.xml file

    Adding the activity will automatically do this, but if it, in some cases, it doesn’t, then follow these instructions. You do this by opening the AndroidManifest.xml file from the following location.

    Once here, you need to find two activity tags in between the application tag.

    If you see the two activity tags, one for each activity, then you are good to go and don’t need to make any changes.

    There will be a bunch of other information too.

    If you don’t see two activity tags, then simply paste the following code below the first activity tag.

    Unless you have named your second Activity something else.

    Now your application recognizes the second activity. But we can’t let it be empty, so let’s add some text and a button to come back on the first activity.

    The interface of the second activity

    The second activity will be completely empty, so we have to add a new text element to show us we are in the second activity, and a button below it to take us back to the previous activity.

    1. Drag and drop a textView element, give it some text like ‘This is the Second Activity.’
    2. Drag and drop a button and give it an ID that you will remember.
    3. Give the button a function name in the onClick option from the properties that you will remember.

    You can find the complete code to the interface of this activity at the bottom of this post.

    Coding the functionality of the application

    You will see that this is by far one of the easiest things to code. Considering that a lot of applications have multiple activities, it shouldn’t be surprising at all. We use two lines of code, each time we want to use the intent.

    Coding the java file of the first activity,

    1. In the first line of code, we describe the intent and give it the source and destination activities.
    2. In the second line, we initialize it.

    Find the entire code of at the bottom of this post.

    Firstly the function name, ‘buttonClick,’ is the same name you gave the button in the properties under onClick. Here, we are creating an object ‘i’ of the class intent, and then we are passing two parameters. The first one is the location where we are right now. We do that by writing in ‘MainActivity.this.’ Then we mention the class name of the activity we want to go to like this ‘Main2Activity.class’.

    In the second line, we have to mention the activity we are in, and run the function startActivity and pass the object’ i’ that we had created in the first line.

    That’s all about it in the first activity.

    Coding the java part of the second activity,

    This is pretty much the same as the code in the first activity. With just the source and destination activities reversed.

    We are doing the same thing as above in this.

    1. Create an object of the intent class.
    2. Add the parameters to the source and destination activities.
    3. Initialize the new activity with the startActivity function.

    How to create an app with android studio

    Most Android apps need to store data somewhere and the most common way to store data on Android is using a SQLite Database.

    We have released a full course on the YouTube channel all about using the SQLite Database with Android Studio. You will learn everything you need to know about SQLite by creating an Android app in Android Studio.

    This course was developed by Shad Sluiter. Shad is a professor of Computer Science at Grand Canyon University. He has been teaching people about technology for over 20 years.

    This course shows every step of programming a demo Android application that uses an SQLlite local database.

    You will learn how to:

    • create an SQLite local database on the Android device,
    • configure new tables with the onCreate method,
    • setup the columns and data types,
    • extend the SQLiteHelper class,
    • create CRUD methods in a DAO (Data Access Object) class,
    • display results on a listview,
    • and more.

    Watch the full course on the YouTube channel (2-hour watch).

    I’m a teacher and developer with I run the YouTube channel.

    If you read this far, tweet to the author to show them you care. Tweet a thanks

    Learn to code for free. freeCodeCamp’s open source curriculum has helped more than 40,000 people get jobs as developers. Get started

    freeCodeCamp is a donor-supported tax-exempt 501(c)(3) nonprofit organization (United States Federal Tax Identification Number: 82-0779546)

    Our mission: to help people learn to code for free. We accomplish this by creating thousands of videos, articles, and interactive coding lessons – all freely available to the public. We also have thousands of freeCodeCamp study groups around the world.

    Donations to freeCodeCamp go toward our education initiatives, and help pay for servers, services, and staff.

    How to create an app with android studio How to create an app with android studio

    How to add Android Device to Android Studio

    In this tutorials, we will see how to add Android Device to Android Studio, so that we can run or test the application on Android Physical Device.

    Android Device to Android Studio :

    We can run Android applications in 2 different modes.

    1. Running on Android Emulator and
    2. Running on Actual Device

    In the previous tutorial, we discussed how to run the android application on emulator, now we will see how to run on our actual Android device (Android Mobile/Tablet).

    Configuring the Android Device :

    1. In your Android Phone Go to Settings and click on About Phone
    2. Where you can see the Build Number, click on build number for 8 times and finally you will be prompted, that You are a Developer!
    3. Now get the USB Cable and connect it to your PC/Workstation.
    4. Go back to Settings in your Android device and search for the Developer Options.
    5. Click on Developer Options, toggle it and Click on OK.

    How to create an app with android studio

    6. Enable OEM Unlocking , Now it will ask you for Screen Lock and After that click on ENABLE.

    What is SHA-1?

    Secure Hash Algorithm 1 or SHA-1 hash value is a unique representation of a certificate. Typically represented as a hexadecimal number with 40 digits long. This fingerprint value is requested by API providers like Google, Facebook along with package name of the app. They use SHA-1 fingerprint for registering the app to use their services securely.

    Since it is a short representation of the developer certificate, it has become an important factor in establishing secure connection between app and service end points.

    Today most of the apps depend on third party services and in future also this trend will continue. So i think this tutorial is relevant and will be helpful for Android developers in generating SHA1 fingerprint value.

    Another reason is to write this tutorial is, many developers are using command-line tool like keytool for generating SHA1 fingerprint but if you are using Android Studio IDE, then you don’t have to use another tools because it is very simple in Android Studio to generate singing fingerprints.

    Gradle is the build system used for Android development in Android studio IDE. Gradle is rich collection of tasks for various purposes. A gradle task named signingReport is responsible for generating fingerprint for the application.

    Running the signingReport task against a particular build variant (debug, release) it will generate SHA-1 fingerprint value. SHA-1 fingerprint value will be different for each build variant. i.e, SHA-1 value of debug will be different from SHA-1 value of release build.

    singingReport task will generate the following fingerprints,

    • MD5
    • SHA1
    • SHA-256

    Note: Best standard out of the above list is, SHA-256

    How To Generate SHA-1 Fingerprint

    Certificate fingerprints can be generated for any build variants like debug, release. Here i explain simple and secure way of generating fingerprint values which involves following 3 processes,

    • Create keystore Properties
    • Load keystore To Gradle
    • Execute Gradle Task

    [Optional] Generate Fingerprints For Release

    If you only want SHA1 fingerprint value for debug build variant then you can skip this section to Step 1.

    By default the gradle task will not generate fingerprints for release build variant. In most places you will only find how to generated certificate fingerprints for debug build variant but if you published your app in Google Play Store then the live version will be a release build. In this case you need to generate certificate fingerprints for release build variant too.

    I will explain how to generate SHA-1 fingerprints for release build variant as well

    If you need fingerprints for release build variant also then you have to do 2 additional things before you jump into build.gradle file,

    • Create a keystore file (file with .jks extension)
    • Add signingConfigs for release

    If you already generated signed build for your app then you can skip keystore file creating part and jump to Step 1 and start creating keystore properties.

    Keystore file is needed for generating signed apk also. So even if we don’t want to generate a signed apk, generating a signed build would be a good idea to get a keystore file.

    Below is the tutorial on how to create a signed apk.

    Step 1. Create Keystore Properties

    Create a file named in the root directory of your project.

    Open the file and past the following content to it.

    Replace the above dummy values with your string values.

    storeFile variable holds the path to where .jks file to be saved. Better create a folder for keystore file and give the full path of the keystore file.

    Step 2. Load KeyStore Properties To Gradle

    Once keystore properties file created with your secret credentials, next step is to load the keystore properties to the gradle build configuration. This will give access to the gradle tasks to the keystore properties.

    Follow the below instructions to load keystore properties,

    In your module’s build.gradle file, add 3 line of code to load your file before the android <> block to load the keystore to gradle.

    Next add keystore properties for release build variant also. To do this, copy paste the release tag into signingConfigs

    If we miss release singingconfigs then Gradle task will not able to generate certificate fingerprints for release build variants.

    Step 3. Execute Gradle Task

    signingReport is the name of task that performs the generation of SHA1 fingerprint. In the latest version of Android Studio,

    FYI here i am using Android Studio 4.2 for the explanation.

    You can find Gradle tab at the right hand-side of the Android Studio IDE. Clicking on the tab will open up the below window.

    How to create an app with android studio

    Click on the Gradle icon (Elephant icon) in the above window. It will open up a sub window,

    How to create an app with android studio

    Type gradle task run command: gradlew singingReport

    Enter the command will start execution of gradle task and generate SHA1, MD5, SHA-256 fingerprints.

    Step 4. Find Generated Fingerprint

    After executing the signingReport you have to open Run tab, which is not selected by default.

    How to create an app with android studio

    Copy the long string shown against SHA1. SHA1 keys are generated and displayed under each build variant i.e, debug, release. Please go to corresponding variant section as shown in the above screenshot.

    If you have added sinigingConfigs for release then you will get release variant also in the above result else, release variant will not be available.

    Thank you. Please comment here if you have any doubt.

    used to give an error for button as below and its solved.

    “cannot implicitly convert type ‘Android.views.view’ to ‘Android.widget.button’. An explicit conversion exist(are you missing cast?)

    Again i got same error in this line.

    “EditText resultText = FindViewById(Resource.Id.resultText);”

    EditText resultText = FindViewById (Resource.Id.resultText); —-DOESNT WORK

    How to create an app with android studio

    How to create an app with android studio

    How to create an app with android studio

    has same problem and, fixed by casting view to a button like this

    Button button1 = (Button)FindViewById(Resource.Id.button1);

    How to create an app with android studio

    Replace line
    Button button1 =FindViewById(Resource.Id.button1);

    Button button1 = (Button) FindViewById(Resource.Id.button1);

    If i want to develop an android application without Xamarian the is it possible?

    I have Windowss8 and WindowsXP PC, If i develop Androip (using VS.NET) then
    Is it possible to run and test on those PC?

    While running the calculator application, I am getting the error “Application does not have a launchable activity”. Please help.
    I think there is something wrong in my AndroidManifest.xml file. Please post your manifest file.

    How to create an app with android studio

    2. Just because the language C# has lambdas doesn’t mean you have to use them always.
    The second you duplicate code because of overuse of lambdas they are the wrong thing to use.
    Also lambdas that are longer then 2 lines are very irritating and hard to debug.

    3. Any function that is longer than a page is probably to long and needs to be refactored.

    How to create an app with android studio

    How to create an app with android studio

    Thank you for the code example – when I run it the application output shows the message

    [Choreographer] Skipped 127 frames! The application may be doing too much work on its main thread.

    How to create an app with android studioGeneral How to create an app with android studioNews How to create an app with android studioSuggestion How to create an app with android studioQuestion How to create an app with android studioBug How to create an app with android studioAnswer How to create an app with android studioJoke How to create an app with android studioPraise How to create an app with android studioRant How to create an app with android studioAdmin

    Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

    Most mobile devices today have built-in sensors such as accelerometers, compasses, temperature, audio and light sensors, GPS etc., that are used in a variety of apps from games to weather and travel apps. The availability of these sensors in mass-marketed mobile devices creates exciting new opportunities for data mining applications.

    This blog is going to show you how to display live accelerometer data in a simple Android seismograph app. To that end we’ll use the Telerik Chart control for Android and we’ll test how the control behaves when handling large amount of streaming data. We’ll build the app using Android Studio and (spoiler alert!) this is the result we’ll get at the end:

    Once you set up a new application (project) in Android Studio, you need to reference the Chart in your Android app. To keep any unnecessary code and logic out of the post I will focus mainly on the workflow and core mechanics of such applications.

    When working with sensors in an Android application, one must first implement the SensorEventListener interface. This interface is used for receiving notifications from the SensorManager when sensor values have changed. Couple of methods have to be overridden – onSensorChanged and onAccuracyChanged. onAccuracyChanged is called when the accuracy of a sensor has changed and onSensorChanged when sensor values have changed. In the case of this seismograph simulator, all the magic will happen in the onSensorChanged override, which is where the acceleration sensor reports its data.

    Let’s start by obtaining a reference to the SensorManager and the accelerometer. As the documentation states, in order to get an instance of the default acceleration sensor, we need to do the following:

    With the above in mind, any similar accelerometer app would inevitably boil down to the following basic workflow:

    How to create an app with android studio

    Leaving out any unnecessary logic, this is how it looks like in code.

    The code above is simplified for illustrative purposes, but is valid for most of the applications of this type. The only thing remaining is to show you how to create the chart.

    This is how you can display data from a smartphone sensor (in this case the accelerometer) inside the Chart.
    The app source code is available for download on GitHub:

    In the next blog post I’ll show you how to add a “needle”. The needle will be synchronized with the Y coordinate of each incoming accelerometer (“seismic”) data point, which will create the following effect:

    Hello friends, Welcome to my new tutorial, and in this tutorial, we will learn how to create AVD in android studio (Android Virtual Device).

    In my previous tutorial, we got to know about What is Android and how to successfully install Android Studio in our System. If you haven’t seen my last post, then you can go ahead with the following link.

    So without any further delay, let’s jump in to the point and learn How to crate AVD in Android studio.

    How To Create AVD in Android Studio

    What is AVD (Android Virtual Device) ?

    • Android virtual device (AVD) also known as the Emulator, is a virtual mobile device which is used to run, test, and debug our android applications on the system without actually using the physical device.
    • Since in Android Studio we create Android Application and to test and debug our apps we need a mobile device but connecting an actual physical device is not that simple in Android studio, and hence Android Studio provides us to create and use Android virtual device which lets us run, test and debug our application.

    So this was the brief information about the Android Virtual device and now let’s know the steps required to create and set up the Android Emulator.


    • Before moving ahead and creating our Android Virtual Device, we need to make sure that all the installation packages are installed successfully.
    • For this purpose, Go to Tools Menu and select the SDK manager.

    How to Create AVD in Android Studio fig – 1

    • Once you clicked on the SDK manager now select the tab SDK tools.

    How to Create AVD in Android Studio fig – 2

    • After selecting the SDK Tools tab, make sure that,
      • Android Emulator is selected and installed.
      • Android SDK Platform-Tools is selected and installed.
      • Android SDK Tools is selected and installed.
      • Intel x86 Emulator Accelerator (HAXM Installer) is selected and installed.

    How to Create AVD in Android Studio fig – 3

    Note – You must also assure that you have enabled the hardware virtualization in your PC’s BIOS and if you don’t know how to do it then you can follow this guide Simple Ways to Enable Hardware Virtualization .

    • After performing all this, we can simply move on to the steps that are required to create an Android Virtual Device.

    Steps to Create AVD in Android Studio

    Step #1

    • Go to Tools Menu and select AVD manager.

    How to Create AVD in Android Studio fig – 4

    Step #2

    • Once you selected the AVD manager, a new window will be opened, and you need to click on the button Create Virtual Device from that window as illustrated in the following image.

    How to Create AVD in Android Studio fig – 5

    Step #3

    • As soon as we click on the Create Virtual Device button, a new window will open, and it will ask us to choose the device definition from the variety of options.

    How to Create AVD in Android Studio fig – 6

    • Since Android Operating System is used in several devices like Phone, Tablet, TV, Watches etc hence we Can also create Android Virtual device for them separately.
    • But For now, we need to select the category as Phone and then we have to choose the name, size of the screen, resolution of the screen and dpi (dots per inch ) as per our requirements for the Emulator.
    • We can also create our own customized android virtual device as per our need by just clicking on the New Hardware Profile Button.

    How to Create AVD in Android Studio fig – 7

    • Once you selected or created your own customized Hardware, just hit the Next button to proceed further.

    Step #4

    • After we click on the Next button, a new window will open, and it will ask us to select a system image to download.
    • As per our need, we can select the API level and then hit the download button to download the system image.

    How to Create AVD in Android fig – 8

    • After you click on the download button, it will start downloading the requested component.

    How to Create AVD in Android fig – 9

    • After it completes downloading the components, click on the Finish button, and then select the image that you have just downloaded and click on the Next button.

    How to Create AVD in Android fig – 10

    Step #5

    • After we click on the Next button, there will be options for us to configure the virtual device.
    • For better performance of the virtual device, we can also make some changes within the Advanced Settings.

    How to Create AVD in Android fig – 11

    • After configuring the virtual device, click on the Finish button.

    Step #6

    • After we click on the Finish Button Android virtual device manager window will open, and now we can run our device by clicking on the play button.

    How to Create AVD in Android fig – 12

    • Now, let’s run our virtual device. For the first time, it may take some time to load the Emulator completely.

    How to Create AVD in Android fig – 13

    • So finally, we have successfully created our Android virtual Device.


    Finally, we have come up with the conclusion that creating an Android Virtual Device in Android Studio is very easy if we follow the right steps otherwise sometimes it may become really tough if we are not aware with the steps.

    So guys, I am wrapping up this tutorial How to Create AVD in Android Studio and feel free to leave us a comment if you find out any hassle while creating AVD in android studio.

    If you don’t want to install a number of programs for building your Android project, this article is for you. You will need only JDK, the Android SDK platform tools and minimum Android platform in order to build apk from command line.

    1. Introduction

    In this article, I will describe how to build Android app from command line, i.e. how to build the .apk file using Android tools and command line. As a result, you can use the batch file for building your Android application. I use Windows commands in this article. But you can use the same Android commands and tools and the same program if you are working on Linux OS. The example of the script for Linux OS is included in the sample project, attached to this article.

    2. Preparation

    Before we build Android .apk from command line, you must install Java JDK and Android SDK on the system where you will build your application. The private keystore also must be present.

    2.1 Java JDK

    You can use Java JDK from Eclipse or download it from this link: and then install it.

    2.2 Android SDK

    Android SDK and its HOWTO document are available here:

    The Android SDK Platform-tools, SDK Platform Android 2.2, and API 8 are the minimum that is needed for the test project work.

    2.3 Environment Variables

    If you want to have a readable batch script and a program without very long file path definitions, you should use the environment variables. I recommend you to define the following ones:

    • JAVABIN path to the Java JDK bin folder. For example: C:\Program Files\Java\jdk\bin. This folder must contain the javac.exe and jarsigner.exe files.
    • ANDROID-SDK path to the Android SDK folder. For example: C:\Program Files\Andoroid\android-sdk-windows.

    2.4 Private Key for Signing

    You can read everything about signing, creating private key, and other operations here:

    In this article, I describe only one important command that will generate my-release-key.keystore:

    Specify your info and you will receive the my-release-key.keystore file. You must remember the password. You will need it later. Also, I recommend you to put the keystore file in the same folder as the project. In the example,It is in the keystore folder in the project directory.

    2.5 Example Files Structure

    You must remember that the dx Android tool requires the full path, which MUST not contain any spaces. So, check the fact, that your project path satisfies the requirement.

    The file structure of the example project, which is built using the build.bat file, is the following:

    3. Command Sequence

    Let’s see how to create an apk file. The following commands are for the Windows OS, but you can create apk from command line for the Linux OS by using the script in the attached sample.

    First of all, we must save current path. Then we must change the CD variable to the path to the build.bat file:

    Then, bin and gen old folders should be recreated:

    I add some definitions. They make the batch file readable and easy to update and thus simplify Android apk development. So, I recommend you the following definitions:

    • minimum Android revision;
    • the path to aapt Android tool and its arguments for adding files into the existing archive;
    • the path to aapt Android tool and its arguments for packing and generating resources;
    • the path to dx Android tool;
    • the path to javac utility of JDK.

    This list of independent definitions can be used for building the majority of Android projects (of course, with the changed Android revision value). For example:

    Also I need the defined variables for my project:

    • APP_NAME is the name of application that will be used for the output APK file.
    • JAVAC_BUILD and JAVAC are the same commands, but there are path to the sources, generated R class, and output folder in JAVAC_BUILD .

    These variables let us change the project name and paths to the sources easier.

    And now, all preparations are finished and the application can be built. The R file will be generated using aapt tool. All resources will be packed into the resources.ap_ file:

    Android manifest file, res and assets folder are the input data. Aapt will generate the R class and put it into the gen folder. Then, aapt will pack the resource files into the resourses.ap_ file.

    Every folder that contains *.java file must be called with javac. In my example, there is only one folder with javac. So, I have only one command line for building sources:

    As you remember, the JAVAC_BUILD command has already contained the arguments that specify the bin folder. The bin folder is an output folder for the compiled sources.

    At this moment, the sources have been compiled successfully and they can be packed in the special dex file:

    For the application signing, the resources file must be copied to another file, which will be used for the signing:

    The classes.dex file must be added to the new file that has an ap_ extension

    Now, the ap_ file is a correct apk file. But it is not signed yet and it cannot be installed to the Android device.

    The creation of the signed Android application from the *.ap_ file is the following (Output file name must differ from the input file name – in this case the file extension is changed to the *.apk):

    And delete temp ap_ file:

    Finally, let’s return to the start folder and clear local variables:

    To test the example and generate apk from command line yourself, you must: