How to make back button twice to close an activity in Android?

Sometimes we click back button unintentionally, When you click on a back button it will close your application or will go back to another activity. To avoid this problem, This example demonstrates how to make back button twice to close an activity.
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:id = "@+id/parent"
   xmlns:tools = "http://schemas.android.com/tools"
   android:layout_width = "match_parent"
   android:layout_height = "match_parent"
   tools:context = ".MainActivity"
   android:gravity = "center"
   android:background = "#33FFFF00"
   android:orientation = "vertical">
   <TextView
      android:id = "@+id/text"
      android:textSize = "18sp"
      android:layout_width = "wrap_content"
      android:layout_height = "wrap_content" />
</LinearLayout>
Step 3 - Add the following code to src/MainActivity.java
package com.example.andy.myapplication;
import android.app.ActivityManager;
import android.content.Context;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.os.VibrationEffect;
import android.os.Vibrator;
import android.support.annotation.RequiresApi;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
   int view = R.layout.activity_main;
   private static final int TIME_INTERVAL = 2000;
   private long mBackPressed;
   @RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN)
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(view);
   }
   @Override
   public void onBackPressed() {
      if (mBackPressed + TIME_INTERVAL > System.currentTimeMillis()) {
         super.onBackPressed();
         return;
      } else {
         Toast.makeText(getBaseContext(), "Click two times to close an activity",    Toast.LENGTH_SHORT).show();
      }
      mBackPressed = System.currentTimeMillis();
   }
}
When a user clicks on the back button it will call onBackpressed(). it going to check two time-pressed or not as shown below -
@Override
public void onBackPressed() {
   if (mBackPressed + TIME_INTERVAL > System.currentTimeMillis()) {
      super.onBackPressed();
      return;
   } else {
      Toast.makeText(getBaseContext(), "Click two times to close an activity", Toast.LENGTH_SHORT).show(); }
      mBackPressed = System.currentTimeMillis();
   }
}
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 -
Once you click on a back button it will show screen as shown above. Now click on twice it will close an application.
Click here to download the project code