Alarm manager

-------------------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" >

    <EditText      

  android:id="@+id/time"  

      android:layout_width="wrap_content"   

     android:layout_height="wrap_content"  

      android:layout_alignParentLeft="true"  

      android:layout_alignParentTop="true"  

      android:layout_marginTop="28dp"      

  android:ems="10"

        android:hint="Number of seconds"  

      android:inputType="numberDecimal" />

    <Button     

   android:id="@+id/button1" 

       android:layout_width="wrap_content"

        android:layout_height="wrap_content" 

       android:layout_alignRight="@+id/time" 

       android:layout_below="@+id/time"   

     android:layout_marginRight="60dp"   

     android:layout_marginTop="120dp"  

      android:text="Start" />

</RelativeLayout>

--------------MainActivity---------------

package com.example.meenakshi.myalarm;

import android.app.Activity;
import android.app.AlarmManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {
    Button b1;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        b1=(Button) findViewById(R.id.button1);

        b1.setOnClickListener(new View.OnClickListener() {

            @Override       
     public void onClick(View v) {
                // TODO Auto-generated method stub    
            startAlert();
            }
        });

    }
    public void startAlert() {
        EditText text = (EditText) findViewById(R.id.time);
        int i = Integer.parseInt(text.getText().toString());
        Intent intent = new Intent(this, MyBroadcastReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(
                this.getApplicationContext(), 234324243, intent, 0);
        AlarmManager alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
        alarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis()
                + (i * 1000), pendingIntent);
        Toast.makeText(this, "Alarm set in " + i + " seconds",Toast.LENGTH_LONG).show();
    }

}

------------MyBroadcastReceiver.CLASS---------

package com.example.meenakshi.myalarm;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Handler;
import android.widget.Toast;

/** * Created by shirsh on 9/15/2017. */
public class MyBroadcastReceiver extends BroadcastReceiver {
    Handler mHandler = new Handler();

    MediaPlayer mp;
    @Override 
   public void onReceive(final Context context, Intent intent) {
        mp=MediaPlayer.create(context, R.raw.shape);


//shape is mp3 song.they add in raw folder
        mp.start();
        Toast.makeText(context, "run...", Toast.LENGTH_SHORT).show();


    }
}

---------AndroidManifest.xml---------------

<receiver android:name=".MyBroadcastReceiver"></receiver>