Question

I’m new on Android developing.
I’m trying to manage gps location between activity. In particular I have created a thread, started with main activity, that update after a few interval the gps position and save the new position into a shared Bean.
Now, when I pass as extras the Bean to the next activity, I can get the last value of the bean but, the bean on the new activity isn’t updated by the thread. I don’t create a new Bean, and for this reason I think that the update of the bean would be seen on the new activity.
There is the code that I use to retrieve the extra in the new activity:

    ShareBean pos;
    Intent intent = getIntent();
    Bundle extras = getIntent().getExtras();
    if (extras != null)
    {
        pos = (ShareBean)intent.getSerializableExtra("Location");
    }

Any help is appreciate.
Thanks in advances.
Simone

Answer 1

you should probably use the LocationManager object to get and access Location updates. You can query it for the last known location for a quick update.

The key things is, I ask the location manager to start listening and then from there I can ask for quick updates anytime. I store the updated location information in my ApplicationContext object (which I call appModel locally) which is persistent throughout the life of the object.

I use the LocationManager like this:

locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
startListening();

Start listening looks like this:

public void startListening() {

    if (gpsLocationListener == null) {
        // make new listeners
        gpsLocationListener = new CustomLocationListener(LocationManager.GPS_PROVIDER);

        // request very rapid updates initially. after first update, we'll put them back down to a much lower frequency
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 60000, 200, gpsLocationListener);
    }

    //get a quick update
    Location networkLocation = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

    //this is the applicationContext object which persists for the life of the applcation
    if (networkLocation != null) {
        appModel.setLocation(networkLocation);
    }
}

You location listener could look like this:

private class CustomLocationListener implements LocationListener {

    private String provider = "";
    private boolean locationIsEnabled = true;
    private boolean locationStatusKnown = true;

    public CustomLocationListener(String provider) {
        this.provider = provider;
    }

    @Override
    public void onLocationChanged(Location location) {
        // Called when a new location is found by the network location provider.
        handleLocationChanged(location);
    }

    public void onStatusChanged(String provider, int status, Bundle extras) {
    }

    public void onProviderEnabled(String provider) {
        startListening();
    }

    public void onProviderDisabled(String provider) {
    }
}

private void handleLocationChanged(Location location) {

    if (location == null) {
        return;
    }

    //get this algorithm from: http://developer.android.com/guide/topics/location/obtaining-user-location.html
    if (isBetterLocation(location, appModel.getLocation())) {
        appModel.setLocation(location);
        stopListening();
    }
}

Good luck!