Question

我一直在遵循以下示例来创建Android服务（具体来说是MQTT服务连接）：Implement Eclipse MQTT Android Client using single connection instance，并且在前景/背景中运行时效果很好，但是在终止应用程序时魔术就结束了。据我了解，它应该重新运行该过程，但事实并非如此，它也不再能够接收消息。

我的MqttConnectionManagerService.class如下：

public class MqttConnectionManagerService extends Service {

    private static final String TAG = "MqttConnectionManagerSe";

    private MqttAndroidClient client;

    @Override
    public void onCreate() {
        super.onCreate();
    }

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }


    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        connect();
        return START_STICKY;
    }

    public void connect() {
        String clientId = MqttClient.generateClientId();
        client = new MqttAndroidClient(getApplication().getApplicationContext(), "tcp://192.168.100.5:1883",
                clientId);
        try {
            IMqttToken token = client.connect();
            client.setCallback(new MqttCallback() {
                @Override
                public void connectionLost(Throwable cause) {

                }

                @Override
                public void messageArrived(String topic, MqttMessage message) {
                    Log.d(TAG, "messageArrived: Topic: " + topic + " Message: " + message);
                }

                @Override
                public void deliveryComplete(IMqttDeliveryToken token) {

                }
            });

            token.setActionCallback(new IMqttActionListener() {
                @Override
                public void onSuccess(IMqttToken asyncActionToken) {
                    Log.d(TAG, "onSuccess: Successfully connected to broker!!!");
                    try {
                        client.subscribe("test", 0, null, new IMqttActionListener() {
                            @Override
                            public void onSuccess(IMqttToken asyncActionToken) {
                                Log.d(TAG, "onSuccess:  Successfully subscribed to topic!!!");
                            }

                            @Override
                            public void onFailure(IMqttToken asyncActionToken, Throwable exception) {

                            }
                        });
                    } catch (MqttException e) {
                        e.printStackTrace();
                    }
                }

                @Override
                public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
                    Log.d(TAG, "onFailure");
                }
            });
        } catch (MqttException e) {
            e.printStackTrace();
        }
    }

}

我的MqttServiceStartReceiver.class：

public class MqttServiceStartReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        context.startService(new Intent(context, MqttConnectionManagerService.class));
    }
}

我的Manifest.xml：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.gshp.mqttpersistencev2">

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

    <application
        android:allowBackup="true"
        android:name=".MqttApplication"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <receiver android:name=".MqttServiceStartReceiver">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
            </intent-filter>
        </receiver>

        <service android:name="org.eclipse.paho.android.service.MqttService" />
        <service android:name=".MqttConnectionManagerService" />
    </application>
</manifest>

我的MainActivity.class：

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    protected void onPostResume() {
        super.onPostResume();
    }

    @Override
    protected void onResume() {
        super.onResume();
        startService(new Intent(this, MqttConnectionManagerService.class));
    }
}

到目前为止，我已经尝试过：创建一个从Application扩展的类，并声明一个等于它的变量，并在实例化MQTT Client（MqttConnectionManagerService.class函数connect()）时将其作为参数传递。 / p>

我真的希望有人能帮助我。

提前谢谢！

MQTT Android客户端服务在关闭应用程序后死亡

0 个答案: