Play Services GCM framework in the Java class library
Play Services GCM framework in the Java class library detailed explanation
Play Services GCM (Google Cloud Messaging) framework is a library for messaging between Android devices.It is a cross -platform push notification solution provided by Google, which aims to help developers integrate real -time notification functions in applications.This article will introduce the main components and usage methods of the Play Services GCM framework in detail, and provide some Java code examples.
1. The main component of the GCM framework
The GCM framework contains the following main components:
1.1. GCM service: GCM service is a cloud message transfer service, responsible for passing the message from the sender to the receiver's device.It provides a stable and reliable connection channel that sends messages to specific devices through the central server provided by Google.
1.2. GCM client API: GCM client API allows developers to register devices in the application to receive GCM messages.It provides a method for sending and receiving messages, as well as the function of managing messages.
1.3. Equipment identifier ID: The device identifier is the unique identifier assigned by the GCM service when the device is registered.It is used to send messages to specific devices.
2. Steps to use Play Services GCM framework
The following are the general steps to use Play Services GCM framework:
2.1. Configuration project: In the Android project, you need to add the dependency relationship of the Google Play Services library and register the GCM service component in the list file.
2.2. Get device identifier: In the application, you need to use the GCM client API to register the device from the GCM to obtain the device identifier.The process of registered devices will be explained in the code example later.
2.3. Send message: Use the method in the GCM client API to send the message to a specific device.The message can contain custom data and display notifications.
2.4. Receive message: Implement GCM broadcast receiver in the application to receive messages from GCM services.The received messages can be used to trigger the user interface of the operation or update the application.The latter code example will show how to achieve the GCM broadcast receiver.
3. GCM code example
The following code example demonstrates how to register devices in Android applications and send messages:
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GoogleApiAvailability;
import com.google.android.gms.gcm.GoogleCloudMessaging;
import com.google.android.gms.iid.InstanceID;
public class GcmHelper {
private static final String SENDER_ID = "your_sender_id";
private static final String SERVER_API_KEY = "your_server_api_key";
public static void registerToGcm(Context context) {
if (checkPlayServices(context)) {
try {
GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(context);
String registrationId = gcm.register(SENDER_ID);
sendRegistrationIdToServer(registrationId);
} catch (IOException e) {
e.printStackTrace();
}
}
}
private static boolean checkPlayServices(Context context) {
GoogleApiAvailability googleApi = GoogleApiAvailability.getInstance();
int resultCode = googleApi.isGooglePlayServicesAvailable(context);
if (resultCode != ConnectionResult.SUCCESS) {
if (googleApi.isUserResolvableError(resultCode)) {
googleApi.getErrorDialog((Activity) context, resultCode, 9000).show();
} else {
Log.e("GcmHelper", "This device is not supported.");
((Activity) context).finish();
}
return false;
}
return true;
}
private static void sendRegistrationIdToServer(String registrationId) {
// Send the device identifier to your server for follow -up processing
// ...
}
}
In the above example, the `registerTogcm` method is used to register the device in the application and obtain the device identifier.`CheckplayServices` method is used to check whether the Google Play service of the device is available.`Sendregificationidtoserver's method is used to send the device identifier to your server for follow -up processing.
Call the registered process of the device at your application's entry activity or starting service where the `GCMHELPER.RegisterTogcm (Context) method is completed.
In addition, you also need to create a GCM broadcast receiver inherited from the `BroadcastReceiver` to receive messages from GCM services.You can ensure that it can receive GCM messages by registering the broadcast receiver in the AndroidManifest.xml file.
Summarize
This article introduces the main components and usage methods of the Play Services GCM framework for the Java developers, and provides a simple registration device and a code for sending messages.By using Play Services GCM framework, developers can easily integrate push notification functions to provide real -time notifications to users of Android applications.
