AlertDialog

AlertDialog can be used to display message with Ok and Cancel buttons. It can be used to interrupt and ask the user about user’s choice to continue or discontinue.

activity_main.xml

<RelativeLayout xmlns:android=”http://schemas.android.com/apk/res/android"
 xmlns:tools=”http://schemas.android.com/tools"
 android:layout_width=”match_parent”
 android:layout_height=”match_parent”
 tools:context=”.MainActivity”>
 
 <Button
 android:id=”@+id/button1"
 android:layout_width=”wrap_content”
 android:layout_height=”wrap_content”
 android:onClick=”onClick”
 android:text=”Click” />
 </RelativeLayout>

MainActvity

package com.example.alertdialog;
 
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {
 
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onClick(View view) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage(“Do you want to close this application?”)
.setCancelable(false)
.setPositiveButton(“Yes”, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
}).setNegativeButton(“No”, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
AlertDialog alert = builder.create();
alert.setTitle(“AlertDialog”);
alert.show();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
} 

Output: