Sensor simulator's NetworkOnMainThreadException

问题

I followed this instruction to debug my app on emulator using sensor simulator: http://code.google.com/p/openintents/wiki/SensorSimulator#How_to_use_the_in_your_application

I completed all steps above, but in my case everything was not as simple as described in instructions. I got NetworkOnMainThreadException trying to connect, register listener etc. So I created async task to solve this problem. Now, I have the following:

connection to simulator:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ...
    sensorManager = SensorManagerSimulator.getSystemService(this, SENSOR_SERVICE);
        this.new ConnectToSimulator().execute();
    }

onResume() listner's registration:

@Override
public void onResume() {
    super.onResume();
    this.new RegisterToSimulator().execute();       
}

finally my tasks:

class ConnectToSimulator extends AsyncTask<Object, Object, Object> {   
    @Override
    protected Object doInBackground(Object... arg0) {
        try{
        sensorManager.connectSimulator();
        }catch(Exception e)
        {
            Log.i("error", e.getMessage());
        }
        return null;
    }       
}

class RegisterToSimulator extends AsyncTask<Object, Object, Object> {      
    @Override
    protected Object doInBackground(Object... arg0) {
        try{
            sensorManager.registerListener(Compass.this, sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_FASTEST);
            sensorManager.registerListener(Compass.this, sensorManager.getDefaultSensor(Sensor.TYPE_MAGNETIC_FIELD), SensorManager.SENSOR_DELAY_FASTEST);
            sensorManager.registerListener(Compass.this, sensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION), SensorManager.SENSOR_DELAY_FASTEST);
        }catch(Exception e)
        {
            Log.i("error", e.getMessage());
        }
        return null;
    }

}

but even after that, I still receive the error trying to launch app on emulator:

12-15 14:23:28.877: E/AndroidRuntime(3724): FATAL EXCEPTION: main 12-15 14:23:28.877: E/AndroidRuntime(3724): android.os.NetworkOnMainThreadException 12-15 14:23:28.877: E/AndroidRuntime(3724): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117) 12-15 14:23:28.877: E/AndroidRuntime(3724): at libcore.io.BlockGuardOs.recvfrom(BlockGuardOs.java:163) 12-15 14:23:28.877: E/AndroidRuntime(3724): at libcore.io.IoBridge.recvfrom(IoBridge.java:513) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.net.PlainSocketImpl.read(PlainSocketImpl.java:488) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.net.PlainSocketImpl.access$000(PlainSocketImpl.java:46) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.net.PlainSocketImpl$PlainSocketInputStream.read(PlainSocketImpl.java:240) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.io.InputStreamReader.read(InputStreamReader.java:244) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.io.BufferedReader.fillBuf(BufferedReader.java:130) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.io.BufferedReader.readLine(BufferedReader.java:354) 12-15 14:23:28.877: E/AndroidRuntime(3724): at org.openintents.sensorsimulator.hardware.SensorSimulatorClient.readSensor(SensorSimulatorClient.java:654) 12-15 14:23:28.877: E/AndroidRuntime(3724): at org.openintents.sensorsimulator.hardware.SensorSimulatorClient.readSensor(SensorSimulatorClient.java:571) 12-15 14:23:28.877: E/AndroidRuntime(3724): at org.openintents.sensorsimulator.hardware.SensorSimulatorClient.access$1000(SensorSimulatorClient.java:53) 12-15 14:23:28.877: E/AndroidRuntime(3724): at org.openintents.sensorsimulator.hardware.SensorSimulatorClient$1.handleMessage(SensorSimulatorClient.java:505) 12-15 14:23:28.877: E/AndroidRuntime(3724): at android.os.Handler.dispatchMessage(Handler.java:99) 12-15 14:23:28.877: E/AndroidRuntime(3724): at android.os.Looper.loop(Looper.java:137) 12-15 14:23:28.877: E/AndroidRuntime(3724): at android.app.ActivityThread.main(ActivityThread.java:5039) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.lang.reflect.Method.invokeNative(Native Method) 12-15 14:23:28.877: E/AndroidRuntime(3724): at java.lang.reflect.Method.invoke(Method.java:511) 12-15 14:23:28.877: E/AndroidRuntime(3724): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 12-15 14:23:28.877: E/AndroidRuntime(3724): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 12-15 14:23:28.877: E/AndroidRuntime(3724): at dalvik.system.NativeStart.main(Native Method)

Can someone clarify why I have so strange error? moreover there is no info in simulator instruction about async task usage necessity, maybe I am doing something wrong. Please help, thanks in advance.

回答1:

Unfortunately this error cannot be bypassed because library is not implemented having "new" SDK limits.

Simplest solution is to set minSdkVersion in manifest to something before Honeycomb (e.g. android:minSdkVersion="8").

Reson for this is, although you did connected on background thread, you still created object on your UI thread, which in return means SensorSimulatorClient will use socket communication on your UI thread.

来源：https://stackoverflow.com/questions/20596091/sensor-simulators-networkonmainthreadexception