PROGRAM 11:
ACTIVITY_MAIN.XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical"
 android:padding="16dp"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
 <EditText
 android:id="@+id/messageEditText"
 android:hint="Enter message"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:inputType="text" />
 <Button
 android:id="@+id/sendButton"
 android:text="Send Message"
 android:layout_width="match_parent"
 android:layout_height="wrap_content"
 android:layout_marginTop="12dp" />
</LinearLayout>
MAINACTIVITY.JAVA
package com.psgcas.myapplication;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Intent;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class MainActivity extends AppCompatActivity {
 private EditText messageEditText;
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 messageEditText = findViewById(R.id.messageEditText);
 Button sendButton = findViewById(R.id.sendButton);
 sendButton.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View view) {
 String message = messageEditText.getText().toString();
 Intent intent = new Intent(MainActivity.this,
SecondActivity.class);
 intent.putExtra("message_key", message);
 startActivity(intent);
 }
 });
 }
}
ACTIVITY_SECOND.XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
 xmlns:android="http://schemas.android.com/apk/res/android"
 android:orientation="vertical"
 android:padding="16dp"
 android:layout_width="match_parent"
 android:layout_height="match_parent">
 <TextView
 android:id="@+id/receivedMessageTextView"
 android:text="Received Message"
 android:textSize="18sp"
 android:layout_width="match_parent"
 android:layout_height="wrap_content" />
</LinearLayout>
SECONDACTIVITY.JAVA
package com.psgcas.myapplication;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.content.Context;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.NotificationCompat;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;
public class SecondActivity extends AppCompatActivity {
 private TextView receivedMessageTextView;
 private final String CHANNEL_ID = "message_channel";
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_second);
 receivedMessageTextView =
findViewById(R.id.receivedMessageTextView);
 String message = getIntent().getStringExtra("message_key");
 receivedMessageTextView.setText(message);
 showNotification(message);
 }
 private void showNotification(String message) {
 NotificationManager notificationManager = (NotificationManager)
getSystemService(Context.NOTIFICATION_SERVICE);
 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
 NotificationChannel channel = new
NotificationChannel(CHANNEL_ID, "Message Notifications",
NotificationManager.IMPORTANCE_DEFAULT);
 notificationManager.createNotificationChannel(channel);
 }
 NotificationCompat.Builder builder = new
NotificationCompat.Builder(this, CHANNEL_ID)
 .setSmallIcon(android.R.drawable.ic_dialog_info)
 .setContentTitle("New Message Received")
 .setContentText(message)
 .setPriority(NotificationCompat.PRIORITY_DEFAULT);
 notificationManager.notify(1, builder.build());
 }
}
ANDROIDMANIFEST.XML
<?xml version="1.0" encoding="utf-8"?>
<manifest
xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:tools="http://schemas.android.com/tools"
 package="com.psgcas.myapplication">
 <uses-permission
android:name="android.permission.POST_NOTIFICATIONS" />
 <application
 android:allowBackup="true"
 android:dataExtractionRules="@xml/data_extraction_rules"
 android:fullBackupContent="@xml/backup_rules"
 android:icon="@mipmap/ic_launcher"
 android:label="@string/app_name"
 android:roundIcon="@mipmap/ic_launcher_round"
 android:supportsRtl="true"
 android:theme="@style/Theme.MyApplication">
 <activity
 android:name=".MainActivity"
 android:exported="true">
 <intent-filter>
 <action android:name="android.intent.action.MAIN" />
 <category android:name="android.intent.category.LAUNCHER" />
 </intent-filter>
 </activity>
 <activity android:name=".SecondActivity" />
 </application>
</manifest>