Creating Alert box or Dialog box in android while onClick button.

This example program is for beginners those who want alert box in their application. I will create a alert box for logout that closes the application. With two options y/n.

To create alert box using xml and customize alert box check this link.

This is how your alert box looks.

I have just place a button in this activity, on-clicking this button pops out a alert box and asks for confirmation for logout.

MainActivity.java : 

package com.exam.sample;




import android.app.Activity;

import android.app.AlertDialog;

import android.content.DialogInterface;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.Toast;




public class MainActivity extends Activity {




@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

Button logout = (Button)findViewById(R.id.button1);

logout.setOnClickListener(new OnClickListener() {

@Override

public void onClick(View v) {

logout();

}

});

}




public void logout(){

AlertDialog.Builder alertDialog = new AlertDialog.Builder(MainActivity.this);

 

alertDialog.setTitle("Logout"); // Sets title for your alertbox



alertDialog.setMessage("Are you sure you want to Logout ?"); // Message to be displayed on alertbox



alertDialog.setIcon(R.drawable.logout1); // Icon for your alertbox




/* When positive (yes/ok) is clicked */

alertDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog,int which) {

finish();

Toast.makeText(MainActivity.this,"Successfully Logged Out", Toast.LENGTH_LONG).show();  

}

});




/* When negative (No/cancel) button is clicked*/

alertDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {

public void onClick(DialogInterface dialog, int which) {

dialog.cancel();

}

});

alertDialog.show();

}

}