Notification

activity_main.xml


<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout 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"
 tools:ignore="Deprecated">
 <Button
 android:id="@+id/idStart"
 android:layout_width="200dp"
 android:layout_height="wrap_content"
 android:layout_x="16dp"
 android:layout_y="16dp"
 android:text="Start Notification"/>
 <Button
 android:id="@+id/idStop"
 android:layout_width="200dp"
 android:layout_height="wrap_content"
 android:layout_x="16dp"
android:layout_y="64dp"
 android:text="Stop Notification"/>
</AbsoluteLayout>


MainActivity.java

package com.example.program7;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.content.Intent;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
 Button start, stop;
 @Override
 protected void onCreate(Bundle b) {
 super.onCreate(b);
 setContentView(R.layout.activity_main);
 start = findViewById(R.id.idStart);
 stop = findViewById(R.id.idStop);
 start.setOnClickListener(this);
 stop.setOnClickListener(this);
 }
 @Override
 public void onClick(View v) {
 if(v.equals(start)) {
 Intent it = new Intent(this,MyService.class);
 startService(it);
 }
 else if(v.equals(stop)) {
 Intent it = new Intent(this, MyService.class);
 stopService(it);
 }
 }
}


MyService.java

package com.example.program7;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.app.Service;
import android.widget.Toast;
import android.content.Intent;
import android.app.Notification;
import android.app.PendingIntent;
import androidx.annotation.NonNull;
import android.app.NotificationManager;
import androidx.core.app.NotificationCompat;
public class MyService extends Service {
 boolean isRunning = false;
 MyThread thread;
 @Override
 public void onCreate() {
 super.onCreate();
 isRunning = true;
 Toast.makeText(getBaseContext(),"Service Created", Toast.LENGTH_SHORT).show();
 thread = new MyThread();
 thread.start();
 }
 @Override
 public int onStartCommand(Intent intent, int flags, int startId) {
 super.onStartCommand(intent, flags, startId);
 Toast.makeText(getBaseContext(),"Service Started", Toast.LENGTH_SHORT).show();
 Bundle b = intent.getBundleExtra("data");
 isRunning = b.getBoolean("stop");
 if(!thread.isAlive()) {
 thread = new MyThread();
 thread.start();
}
 return Service.START_NOT_STICKY;
 }
 @Override
 public IBinder onBind(Intent intent) {
 return null;
 }
 @Override
 public void onDestroy() {
 isRunning = false;
 Toast.makeText(getBaseContext(),"Service Stopped", Toast.LENGTH_SHORT).show();
 super.onDestroy();
 }
 Handler hand = new Handler(){
 @Override
 public void handleMessage(@NonNull Message msg) {
 NotificationManager manager=(NotificationManager)getSystemService(NOTIFICATION_SERVICE);
 NotificationCompat.Builder builder=new NotificationCompat.Builder(getBaseContext());
 builder.setContentTitle("From Service");
 builder.setContentText("Hi! " + msg.what);
 builder.setSmallIcon(R.drawable.ic_launcher_foreground);
 builder.setContentIntent(PendingIntent.getActivity(getBaseContext(), 1, new
Intent(getBaseContext(),MainActivity.class),Intent.FILL_IN_ACTION));
 manager.notify(1, builder.build());
 }
 };
 private class MyThread extends Thread {
 @Override
 public void run() {
 int i = 0;
 while (isRunning){
 try {
 Thread.sleep(5000);
 }
 catch(InterruptedException e) {
e.printStackTrace();
 }
 hand.sendEmptyMessage(i++);
 }
 }
 }
}



AndroidManifest.xml

<service
 android:name=".MyService"
 android:enabled="true"
 android:exported="true"/>