我想将消息从
android服务发布到本地服务器.这是我的代码的一部分,最简单的形式基于
here的片段.
MemoryPersistence memPer;
MqttAndroidClient client;
@Override
public IBinder onBind(Intent intent) {
memPer = new MemoryPersistence();
client = new MqttAndroidClient(this,"tcp://192.168.1.42:1883","clientid",memPer);
try {
client.connect(null,new IMqttActionListener() {
@Override
public void onSuccess(IMqttToken mqttToken) {
Log.i("MQTT","Client connected");
Log.i("MQTT","Topics=" + mqttToken.getTopics());
MqttMessage message = new MqttMessage("Hello,I am Android Mqtt Client.".getBytes());
message.setQos(2);
message.setRetained(false);
try {
client.publish("messages",message);
Log.i("MQTT","Message published");
client.disconnect();
Log.i("MQTT","client disconnected");
} catch (MqttPersistenceException e) {
// Todo Auto-generated catch block
e.printstacktrace();
} catch (MqttException e) {
// Todo Auto-generated catch block
e.printstacktrace();
}
}
@Override
public void onFailure(IMqttToken arg0,Throwable arg1) {
// Todo Auto-generated method stub
Log.i("MQTT","Client connection Failed: " + arg1.getMessage());
}
});
} catch (MqttException e) {
e.printstacktrace();
}
return mBinder;
}
但总是调用onFailure函数,我得到错误：
I/MQTT﹕ Client connection Failed: cannot start service org.eclipse.paho.android.service.MqttService
显然由库返回,因为’listener！= null’,Line 410.使用调试器,它显示’listener = SensorLoggerService $1 @ 3634′. SensorLoggerService是我的服务.
什么可能出错？非常感谢.
解决方法
对我来说同样的问题,在我的情况下问题是< service>标签位于< application>之外标签.
一开始我有这个：
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mycompany.myapp" >
...
<service android:name="org.eclipse.paho.android.service.MqttService">
</service>
...
<application
android:name="com.mycompany.myapp" ... >
...
</application>
然后我改为：
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mycompany.myapp" >
...
<application
android:name="com.mycompany.myapp" ... >
...
<service android:name="org.eclipse.paho.android.service.MqttService">
</service>
</application>
一切正常！
您还需要添加INTERNET和ACCESS_NETWORK_STATE权限,否则您将无法连接.
HTH