Normally an error while doing something on the UI thread from another thread I thought, but I don't get what I'm doing wrong. The error seems only to appear when the phone is travelling, so with a changing GPS location.
I want the most recent location to be stored, so nothing on the UI. I have the following method called from the main activity:
public void getFreshDeviceLocation(long interval, final long maxtime) {
if (gps_recorder_running){return;}
gpsTimer = new Timer();
//starts location
startMillis=System.currentTimeMillis();
// receive updates
for (String s : locationManager.getAllProviders()) {
LocationListener listener=new LocationListener() {
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onLocationChanged(Location location) {
// if this is a gps location, we can use it
if (location.getProvider().equals(
LocationManager.GPS_PROVIDER)) {
doLocationUpdate(location, true); //stores the location in the prefs
stopGPS();
}
}
@Override
public void onStatusChanged(String provider,
int status, Bundle extras) {
// TODO Auto-generated method stub
}
};
locationManager.requestLocationUpdates(s, interval, //line 97, error!
minDistance, listener);
myListeners.add(listener);
gps_recorder_running = true;
}
// start the gps receiver thread
gpsTimer.scheduleAtFixedRate(new TimerTask() {
@Override
public void run() {
Location location = getBestLocation();
doLocationUpdate(location, false);
if ((System.currentTimeMillis()-startMillis)>maxtime){if (maxtime>0){stopGPS();}}
//Updates depend on speed of the device
float speed=pref.DeviceLocation().getSpeed();
if (speed<1){if (speedclass!=0){speedclass=0;stopGPS();getFreshDeviceLocation(300000,0);}}
if ((speed>=1)&&(speed<3)){if (speedclass!=1){speedclass=1;stopGPS();getFreshDeviceLocation(90000,0);}}
if ((speed>=3)&&(speed<17)){if (speedclass!=2){speedclass=2;stopGPS();getFreshDeviceLocation(15000,0);}}
if (speed>=17){if (speedclass!=3){speedclass=3;stopGPS();getFreshDeviceLocation(10000,0);}}
}
}, 0, interval);
}
The error I get is:
java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:121)
at android.location.LocationManager$ListenerTransport$1.<init>(LocationManager.java:139)
at android.location.LocationManager$ListenerTransport.<init>(LocationManager.java:137)
at android.location.LocationManager._requestLocationUpdates(LocationManager.java:708)
at android.location.LocationManager.requestLocationUpdates(LocationManager.java:630)
at com.appiclife.tmoflashlight.TMO_LocationManager.getFreshDeviceLocation(TMO_LocationManager.java:97)
at com.appiclife.tmoflashlight.TMO_LocationManager$2.run(TMO_LocationManager.java:116)
at java.util.Timer$TimerImpl.run(Timer.java:289)
Line 97=locationManager.requestLocationUpdates(s, interval,minDistance, listener); (LocationManager class)
Seems like I have to call Looper.prepare(); and Looper.loop(); somewhere, but I don't see where? It might have something to do with this question AsyncTask and Looper.prepare() error
In this case, I think what you need is a looper thread, this may help you.
Or you may create a handler inside your run() method make it a looper thread as the following example.
Handler mHandler;
public void run(){
Looper.prepare();
mHandler = new Handler(){
public void handleMessage(Message msg){
Looper.myLooper().quit();
}
};
//do your stuff
//...
mHandler.sendEmptyMessage(0); //send ourself a message so the looper can stop itself
Looper.loop();
}//end of run
Please let me know if it helps :)