Using a Mock Location in Navigation App
I'm trying to develop an application that will simulate a route through Google's Navigation application. I found some excellent examples of how to implement a mock location provider in some other posts on this website ( Android mock location on device? ).
With a simple modification to the source code http://www.cowlumbus.nl/forum/MockGpsProvider.zip, my mock location shows up in Google's Maps application. (The only change is the mock provider name to LocationManager.GPS_PROVIDER). My problem is that when I open the Navigation app, it says "Searching for GPS signal." I still see my location moving across the map; however, it doesn't generate a route to the destination. I was wondering if anyone knows what I need to do to fake Navigation into see my mock location as the GPS signal. Thanks.public class MockGpsProviderActivity extends Activity implements LocationListener {
private MockGpsProvider mMockGpsProviderTask = null;
private Integer mMockGpsProviderIndex = 0;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
String mocLocationProvider = LocationManager.GPS_PROVIDER;
locationManager.addTestProvider(mocLocationProvider, false, false,
false, false, true, false, false, 0, 5);
locationManager.setTestProviderEnabled(mocLocationProvider, true);
locationManager.requestLocationUpdates(mocLocationProvider, 0, 0, this);
try {
List<String> data = new ArrayList<String>();
InputStream is = getAssets().open("test.csv");
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
String line = null;
while ((line = reader.readLine()) != null) {
data.add(line);
}
// convert to a simple array so we can pass it to the AsyncTask
String[] coordinates = new String[data.size()];
data.toArray(coordinates);
// create new AsyncTask and pass the list of GPS coordinates
mMockGpsProviderTask = new MockGpsProvider();
mMockGpsProviderTask.execute(coordinates);
}
catch (Exception e) {}
}
@Override
public void onDestroy() {
super.onDestroy();
// stop the mock GPS provider by calling the 'cancel(true)' method
try {
mMockGpsProviderTask.cancel(true);
mMockGpsProviderTask = null;
}
catch (Exception e) {}
// remove it from the location manager
try {
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.removeTestProvider(MockGpsProvider.GPS_MOCK_PROVIDER);
}
catch (Exception e) {}
}
@Override
public void onLocationChanged(Location location) {
// show the received location in the view
TextView view = (TextView) findViewById(R.id.text);
view.setText( "index:" + mMockGpsProviderIndex
+ "\nlongitude:" + location.getLongitude()
+ "\nlatitude:" + location.getLatitude()
+ "\naltitude:" + location.getAltitude() );
}
@Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
/** Define a mock GPS provider as an asynchronous task of this Activity. */
private class MockGpsProvider extends AsyncTask<String, Integer, Void> {
public static final String LOG_TAG = "GpsMockProvider";
public static final String GPS_MOCK_PROVIDER = "GpsMockProvider";
/** Keeps track of the currently processed coordinate. */
public开发者_如何学Go Integer index = 0;
@Override
protected Void doInBackground(String... data) {
// process data
for (String str : data) {
// skip data if needed (see the Activity's savedInstanceState functionality)
if(index < mMockGpsProviderIndex) {
index++;
continue;
}
// let UI Thread know which coordinate we are processing
publishProgress(index);
// retrieve data from the current line of text
Double latitude = null;
Double longitude = null;
Double altitude= null;
try {
String[] parts = str.split(",");
latitude = Double.valueOf(parts[0]);
longitude = Double.valueOf(parts[1]);
altitude = Double.valueOf(parts[2]);
}
catch(NullPointerException e) { break; } // no data available
catch(Exception e) { continue; } // empty or invalid line
// translate to actual GPS location
Location location = new Location(LocationManager.GPS_PROVIDER);
location.setLatitude(latitude);
location.setLongitude(longitude);
location.setAltitude(altitude);
location.setTime(System.currentTimeMillis());
// show debug message in log
Log.d(LOG_TAG, location.toString());
// provide the new location
LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.setTestProviderLocation(LocationManager.GPS_PROVIDER, location);
// sleep for a while before providing next location
try {
Thread.sleep(200);
// gracefully handle Thread interruption (important!)
if(Thread.currentThread().isInterrupted())
throw new InterruptedException("");
} catch (InterruptedException e) {
break;
}
// keep track of processed locations
index++;
}
return null;
}
@Override
protected void onProgressUpdate(Integer... values) {
Log.d(LOG_TAG, "onProgressUpdate():"+values[0]);
mMockGpsProviderIndex = values[0];
}
}
}
Here is what I was missing:
location.setLatitude(latitude);
location.setLongitude(longitude);
location.setAccuracy(16F);
location.setAltitude(0D);
location.setTime(System.currentTimeMillis());
location.setBearing(0F);
Also, it is important to calcaulte the bearing for navigation. Otherwise, the route updates will be inaccurate.
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