Android :Creating a Alert Message Box (Toast)

Creating a Alert Message Box

Code Here : 

               AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                builder.setTitle("Alert Dialog");
                builder.setMessage("Welcome to Android Application");
                builder.setPositiveButton("OK", null);
                builder.show();

Code to Display Toast when OK button is pressed

                AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                builder.setTitle("Alert Dialog");
                builder.setMessage("Welcome to Android Application");
               
                builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {

                     public void onClick(DialogInterface dialog,int which)
                     {
              Toast.makeText(getApplicationContext(),"You clicked on OK",   Toast.LENGTH_SHORT).show();        
                     }

example 2:

 Add a button to activity_main.xml

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button oButton=(Button)findViewById(R.id.button);
        oButton.setOnClickListener(
                new Button.OnClickListener(){
                    public void onClick(View v){
                        new misc().alert_box("hi","hi",MainActivity.this);
                    }
                }
        );
    }
} 

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package com.example.dejayapr.test1;
import android.app.AlertDialog;
import android.content.Context;

class misc {

    public void alert_box(String title,String message,Context c){
        AlertDialog alertDialog = new AlertDialog.Builder(c).create();
        alertDialog.setTitle(title);
        alertDialog.setMessage(message);
        alertDialog.show();
    }
} 

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