How to use handler in android?

This example demonstrate about How to use handler in 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.

<?xml version = "1.0" encoding = "utf-8"?>
<LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android"
   android:orientation = "vertical"
   android:layout_width = "match_parent"
   android:layout_height = "match_parent">
   <Button
      android:id = "@+id/my_button"
      android:layout_width = "100dp"
      android:layout_height = "wrap_content"
      android:layout_x = "0dp"
      android:layout_y = "0dp"
      android:text = "Yes" />
</LinearLayout>

In the above code, we have taken button.

Step 3 − Add the following code to src/MainActivity.java

<?xml version = "1.0" encoding = "utf-8"?>
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.FragmentActivity;
import android.util.DisplayMetrics;
import android.widget.Button;
import java.util.Random;
import java.util.Timer;
import java.util.TimerTask;

public class MainActivity extends FragmentActivity {
   Handler handler;
   @Override
   public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      handler = new Handler();
      final Button button = (Button) findViewById(R.id.my_button);
      final DisplayMetrics displaymetrics = new DisplayMetrics();
      getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
      final Timer timer = new Timer();
      timer.schedule(new TimerTask() {
         @Override
         public void run() {
            handler.post(new Runnable() {
               @Override
               public void run() {
                  Random R = new Random();
                  final float dx = R.nextFloat() * displaymetrics.widthPixels;
                  final float dy = R.nextFloat() * displaymetrics.heightPixels;
                  final Timer timer = new Timer();
                  button.animate()
                  .x(dx)
                  .y(dy)
                  .setDuration(0)
                  .start();
               }
            });
         }
      }, 0, 1000);
   }
}

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 Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen –

Click here to download the project code