The technical principles of the Play Services GCM framework in the Java class library
Analysis of the technical principles of the Play Services GCM framework in the Java class library
Overview:
Play Services GCM (Google Cloud Messaging) is a service framework provided by Google to pass messages between Android applications.When using the GCM framework in the Java library, following specific technical principles can help developers achieve more reliable, efficient and secure communication.This article will in -depth analysis of the technical principles of the Play Services GCM framework in the Java library and provide corresponding code examples.
Technical principles analysis:
1. Use Google Play service library: In order to use the GCM framework, we must first ensure that the Google Play service library is correctly integrated.Use Gradle to build tools in the Android project, which can be introduced into the library by adding dependencies to the built.gradle file.The following is an example:
dependencies {
implementation 'com.google.android.gms:play-services-gcm:17.0.0'
}
2. Configure Manifest file: The GCM framework needs to be configured in the manifest file of the application.The corresponding permission and service statement must be added, and the service category of the package name and processing the receiving message is specified.The following is an example:
<manifest>
<permission android:name="<your_package_name>.permission.C2D_MESSAGE"
android:protectionLevel="signature" />
<uses-permission android:name="<your_package_name>.permission.C2D_MESSAGE" />
<application>
<service
android:name=".GcmMessageHandler"
android:exported="false">
<intent-filter>
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
</intent-filter>
</service>
<receiver
android:name=".GcmBroadcastReceiver"
android:permission="com.google.android.c2dm.permission.SEND">
<intent-filter>
<action android:name="com.google.android.c2dm.intent.REGISTRATION" />
<category android:name="<your_package_name>" />
</intent-filter>
</receiver>
</application>
</manifest>
3. Registration device: When the application starts, the registered device is required to obtain the unique device identifier.Developers can create a separate class, responsible for handling the logic of equipment registration, and call the register method provided by the GCM framework at appropriate.The following is an example:
public class GcmRegistrationUtil {
// Define the name of the ACTION name for broadcast processing results
public static final String REGISTRATION_COMPLETE = "registrationComplete";
// Register equipment
public void registerDevice(Context context) {
GoogleApiAvailability api = GoogleApiAvailability.getInstance();
int resultCode = api.isGooglePlayServicesAvailable(context);
if (resultCode == ConnectionResult.SUCCESS) {
Intent intent = new Intent(REGISTRATION_COMPLETE);
String regId = FirebaseInstanceId.getInstance().getToken();
intent.putExtra("registrationId", regId);
LocalBroadcastManager.getInstance(context).sendBroadcast(intent);
}
}
}
4. Receive and processing messages: In the application, receiving and processing GCM messages need to create a service class that inherits from GCMListenerService.Through the method of rewriting the class, developers can customize the receiving messages.The following is an example:
public class GcmMessageHandler extends GcmListenerService {
@Override
public void onMessageReceived(String from, Bundle data) {
String message = data.getString("message");
// Customize the receiving message received
// ...
// Display notification to the notification column
sendNotification(message);
}
private void sendNotification(String message) {
// Construction notice
NotificationCompat.Builder builder = new NotificationCompat.Builder(this)
.setSmallIcon(R.drawable.notification_icon)
.setContentTitle("GCM Notification")
.setContentText(message)
.setPriority(NotificationCompat.PRIORITY_DEFAULT)
.setAutoCancel(true);
// Display notification
NotificationManagerCompat notificationManager = NotificationManagerCompat.from(this);
notificationManager.notify(0, builder.build());
}
}
in conclusion:
This article detailed the technical principles of using the Play Services GCM framework in the Java library and provided the corresponding code example.By following these principles, developers can implement reliable, efficient and secure message transmission functions in Android applications.
