使用Firebase在Android设备上发送推送通知(FCM)

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WAKE_LOCK" />

<service
    android:name=".MyFirebaseMessagingService"
    android:exported="false">
    <intent-filter>
        <action android:name="com.google.firebase.MESSAGING_EVENT" />
    </intent-filter>
</service>

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        // 处理接收到的消息
        if (remoteMessage.getNotification() != null) {
            // 显示通知
            showNotification(remoteMessage.getNotification().getTitle(), remoteMessage.getNotification().getBody());
        }
    }

    private void showNotification(String title, String body) {
        // 创建并显示通知
        NotificationCompat.Builder builder = new NotificationCompat.Builder(this, "channel_id")
                .setContentTitle(title)
                .setContentText(body)
                .setSmallIcon(R.drawable.ic_notification);

        NotificationManagerCompat notificationManager = NotificationManagerCompat.from(this);
        notificationManager.notify(0, builder.build());
    }
}