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POGPS location once
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copied!<p>I have an app that finds the users location (loading in a progress dialog) using GPS or network signal , when it finds it's location, the coordinates are written in a text view . If the GPS doesn't find a location in 40 sec or the user clicks on the cancel button , then the dialog closes. The problem is that if I click to cancel the dialog , it doesn't dismiss. However, if I click again, it dismisses. Why do I have to click twice ?!? Below is the source code: </p> <pre><code>public class MainActivity extends Activity { private LocationControl locationControlTask; private boolean hasLocation = false; LocationHelper locHelper; protected Location currentLocation; private TextView myText; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); myText = (TextView)findViewById(R.id.mytext); locHelper = new LocationHelper(); locHelper.getLocation(MainActivity.this, locationResult); locationControlTask = new LocationControl(); locationControlTask.execute(this); } protected void onStart() { super.onStart(); // .... new LocationControl().execute(this); } private class LocationControl extends AsyncTask<Context, Void, Void> { private final ProgressDialog dialog = new ProgressDialog(MainActivity.this); protected void onPreExecute() { this.dialog.setMessage("Tap to cancel"); this.dialog.setTitle("Searching"); this.dialog.setCancelable(true); this.dialog.setButton(Dialog.BUTTON_NEGATIVE, "Cancel", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { if(which == Dialog.BUTTON_NEGATIVE) { dialog.dismiss(); Toast.makeText(MainActivity.this, "dialog canceled", Toast.LENGTH_SHORT).show(); } } }); this.dialog.show(); } protected Void doInBackground(Context... params) { //Wait 40 seconds to see if we can get a location from either network or GPS, otherwise stop Long t = Calendar.getInstance().getTimeInMillis(); while (!hasLocation && Calendar.getInstance().getTimeInMillis() - t < 40000) { try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } }; return null; } protected void onPostExecute(final Void unused) { if(this.dialog.isShowing()) { this.dialog.dismiss(); } if (currentLocation != null) { //useLocation(); String text = "lat:"+currentLocation.getLatitude()+" long:"+currentLocation.getLongitude(); myText.setText(text); } else { Toast.makeText(MainActivity.this, "location could not be found", Toast.LENGTH_SHORT).show(); //Couldn't find location, do something like show an alert dialog } } } public LocationResult locationResult = new LocationResult() { @Override public void gotLocation(final Location location) { currentLocation = new Location(location); hasLocation = true; } }; @Override protected void onStop() { locHelper.stopLocationUpdates(); locationControlTask.cancel(true); super.onStop(); } } </code></pre> <p>The location helper: </p> <pre><code>public class LocationHelper { LocationManager locationManager; private LocationResult locationResult; boolean gpsEnabled = false; boolean networkEnabled = false; public boolean getLocation(Context context, LocationResult result) { locationResult = result; if(locationManager == null) { locationManager = (LocationManager)context.getSystemService(Context.LOCATION_SERVICE); } //exceptions thrown if provider not enabled try { gpsEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER); } catch (Exception ex) {} try { networkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER); } catch (Exception ex) {} //dont start listeners if no provider is enabled if(!gpsEnabled && !networkEnabled) { return false; } if(gpsEnabled) { locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps); } if(networkEnabled) { locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork); } //GetLastLocation(); return true; } LocationListener locationListenerGps = new LocationListener() { public void onLocationChanged(Location location) { locationResult.gotLocation(location); locationManager.removeUpdates(this); locationManager.removeUpdates(locationListenerNetwork); } public void onProviderDisabled(String provider) {} public void onProviderEnabled(String provider) {} public void onStatusChanged(String provider, int status, Bundle extra) {} }; LocationListener locationListenerNetwork = new LocationListener() { public void onLocationChanged(Location location) { locationResult.gotLocation(location); locationManager.removeUpdates(this); locationManager.removeUpdates(locationListenerGps); } public void onProviderDisabled(String provider) {} public void onProviderEnabled(String provider) {} public void onStatusChanged(String provider, int status, Bundle extra) {} }; private void GetLastLocation() { locationManager.removeUpdates(locationListenerGps); locationManager.removeUpdates(locationListenerNetwork); Location gpsLocation = null; Location networkLocation = null; if(gpsEnabled) { //if() gpsLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); } if(networkEnabled) { networkLocation = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); } //if there are both values use the latest one if(gpsLocation != null && networkLocation != null) { if(gpsLocation.getTime() > networkLocation.getTime()) { locationResult.gotLocation(gpsLocation); } else { locationResult.gotLocation(networkLocation); } return; } if(gpsLocation != null) { locationResult.gotLocation(gpsLocation); return; } if(networkLocation != null) { locationResult.gotLocation(networkLocation); return; } //locationResult.gotLocation(null); } public void stopLocationUpdates() { locationManager.removeUpdates(locationListenerGps); locationManager.removeUpdates(locationListenerNetwork); } public static abstract class LocationResult { public abstract void gotLocation(Location location); } } </code></pre> <p>the xml :</p> <pre><code><?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:id="@+id/mytext" android:textSize="15dip" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:text="Main activity"/> </LinearLayout> </code></pre> <p>and these 2 permissions in manifest </p> <pre><code><uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> </code></pre> <p>I would appreciate it if anyone would take a look at the bug.</p>

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