Confirm to Quit? Over-write the BACK key.

To over-write the BACK key, to prompt user for confirmation to quit instead of exiting directly, simply override the onBackPressed() method.

package com.exercise.AndroidConfirmQuit;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;

public class AndroidConfirmQuitActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
    
 @Override
 public void onBackPressed() {
  // TODO Auto-generated method stub
  //super.onBackPressed();
  openQuitDialog();
 }
 
 private void openQuitDialog(){
  AlertDialog.Builder quitDialog 
   = new AlertDialog.Builder(AndroidConfirmQuitActivity.this);
  quitDialog.setTitle("Confirm to Quit?");
  
  quitDialog.setPositiveButton("OK, Quit!", new OnClickListener(){

   @Override
   public void onClick(DialogInterface dialog, int which) {
    // TODO Auto-generated method stub
    finish();
   }});
  
  quitDialog.setNegativeButton("NO", new OnClickListener(){

   @Override
   public void onClick(DialogInterface dialog, int which) {
    // TODO Auto-generated method stub
    
   }});
  
  quitDialog.show();
 }
}