Question

我在GCM遇到问题，所以我迁移到FCM，但我仍然遇到与令牌相关的问题。

我启动了更新后的应用，并检查了有300个新用户，其中200个获得了令牌，100个没有获得任何令牌，这是一个非常关键的问题。

null令牌的任何解决方案？

Answer 1

每次全新安装时，都会从MyInstanceIDListenerService类onTokenRefresh（）方法获取FCM令牌。

或者您也可以使用以下代码获取FCM令牌：

FirebaseInstanceId.getInstance().getToken();

Answer 2

     class MyFirebaseInstanceIdService extends FirebaseInstanceIdService {

            private static final String TAG = "MyFirebaseIIDService";

            @Override
            public void onTokenRefresh() {

                //Getting registration token
                String refreshedToken = FirebaseInstanceId.getInstance().getToken();

                //Displaying token in logcat
                Log.e(TAG, "Refreshed token: " + refreshedToken);

            }

            private void sendRegistrationToServer(String token) {
                //You can implement this method to store the token on your server
                //Not required for current project
            }
        }

     **Sometimes tokens are not generated then write this code**

public class ContCreateTokenService extends Service {
            @Nullable
            @Override
            public IBinder onBind(Intent intent) {
                return null;
            }

            @Override
            public int onStartCommand(Intent intent, int flags, int startId) {
                Intent serviceIntent = new Intent(this, MyFirebaseMessagingService.class);
                startService(serviceIntent);
                return START_REDELIVER_INTENT;
            }
        }

public class FetchNewRefreshToken extends IntentService {
    /**
     * Creates an IntentService.  Invoked by your subclass's constructor.
     *
     * @param name Used to name the worker thread, important only for debugging.
     */

    public static final String TAG = FetchNewRefreshToken.class.getSimpleName();


    public FetchNewRefreshToken() {
        super(TAG);
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        try {

            // Resets Instance ID and revokes all tokens.
            FirebaseInstanceId.getInstance().deleteInstanceId();


            // Now manually call onTokenRefresh()
            Log.e(TAG, "Getting new token");
            FirebaseInstanceId.getInstance().getToken();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

同时将其添加到Menifest文件

中

 <service android:name=".ContCreateTokenService" />
 <service android:name=".FetchNewRefreshToken " />

在启动活动中： -

 startService(new Intent(this, FetchNewRefreshToken.class));
 startService(new Intent(this, ContCreateTokenService.class));

FCM令牌不会在某些Android设备中生成

2 个答案: