How to Add AlertDialog in Android

Introduction

In this article, we will see how to add an AlertDialog in Android.

Procedure

Start the Eclipse IDE.
Create a new project.
Create a MainActivity.java file.
Create an activity_main.xml file for layout design.
Add a button in the XML layout.
Then look up the button by its id in the MainActivity.java file.
Create an object like this: AlertDialog.Builder a1=new AlertDialog.Builder(this);

The code for the example is given below.

MainActivity.java

package com.example.aadialogtodayyy;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.os.Bundle;
import android.os.Process;
import android.view.KeyEvent;
import android.view.View;
import android.widget.Button;
public class MainActivity extends Activity implements android.view.View.OnClickListener
{
Button b1;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b1=(Button) findViewById(R.id.button1);
b1.setOnClickListener(this);
}
public void adddddd()
{
AlertDialog.Builder a1=new AlertDialog.Builder(this);
a1.setTitle("Exit from Abhijeet's Application");
a1.setMessage("Are u sure ?");
a1.setIcon(getResources().getDrawable(R.drawable.ic_launcher));
a1.setPositiveButton("Yes", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
finish();
}
});
a1.setNegativeButton("No", new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
Process.killProcess(Process.myPid());
}
});
a1.show();
}
public void onClick(View v) {
// TODO Auto-generated method stub
adddddd();
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if(keyCode==KeyEvent.KEYCODE_MENU)
{
adddddd();
}
// TODO Auto-generated method stub
return super.onKeyDown(keyCode, event);
}
}

Activity_main.xml

Output