Java Development

[amiz]

My app uses code from the GPS demo and am trying to acquire location using cellsites.

I am seeing two issues:

1. The code works on a 9550 simulator but does not return from a getLocation(-1) call on a Bold 9700 device

2. When in setupCriteria I use, the code hangs on that line.

Any pointers will be appreciated.

thanks

//myCriteria = new BlackBerryCriteria(GPSInfo.GPS_MODE_CELLSITE);

The code looks like this:

private void setupCriteria(){
	_criteria = new Criteria();
	_criteria.setHorizontalAccuracy(Criteria.NO_REQUIREMENT);
	_criteria.setVerticalAccuracy(Criteria.NO_REQUIREMENT);
	_criteria.setCostAllowed(true);
	_criteria.setPreferredPowerConsumption(Criteria.POWER_USAGE_LOW);
	//myCriteria = new BlackBerryCriteria(GPSInfo.GPS_MODE_CELLSITE);
}


private void createLocationProvider(){
	try {			
		_provider = LocationProvider.getInstance(myCriteria);
	} catch (LocationException e) {			
		status("Error in location acquisition");
	}
}	

private void getSingleFix(){		
	new Thread(){
		public void run(){
		       resetProvider();				
			setupCriteria();
			createLocationProvider();
			try {
			_location =_provider.getLocation(-1);	
		} catch (LocationException e) {				
			status("Error in location acquisition");
			} catch (InterruptedException e) {
			status("Error in location acquisition");
			}

			if(_location!=null && _location.isValid()){
			QualifiedCoordinates coordinates = _location.getQualifiedCoordinates();
			double lat = coordinates.getLatitude();
			double longit = coordinates.getLongitude();
			latlong(lat, longit);				status(" ");
				log("In loc valid");

					
			} else{
				status("Error in location acquisition");
			}
		}
	}.start();				
}	
private void resetProvider(){
	if(_provider!=null){
		_provider.setLocationListener(null, 0, 0, 0);
		_provider.reset();
		_provider=null;
	}
}
	
public void locationUpdated(LocationProvider provider, Location location) {
	if(location!=null && location.isValid()){
		QualifiedCoordinates coordinates = location.getQualifiedCoordinates();
		double lat = coordinates.getLatitude();
		double longit = coordinates.getLongitude();
		latlong(lat, longit);
		status(" ");			
	} else{
		status("Error in location acquisition");
	}				
}
	
public void providerStateChanged(LocationProvider provider, int newState) {
		/**
		 * not implemented. For more information on how to implement this method please
		 * refer to the BlackBerry Developer Knowledge Base Articles.
		 */

}

[NOTiFYPiNPOiNT · Accepted solution]

Try setting Power Consumption to High and see if that works.

My GPS app appears to either hang or throw a null pointer exception when I try and use  Power Consumptin set to low on my BB 9700.

criteria.setPreferredPowerConsumption(

Criteria.POWER_USAGE_HIGH);

[amiz]

Setting POWER_USAGE_HIGH made it work.

Thanks

[amiz]

Testing the fix inside a building where there's no GPS, sometimes it works and other times it does not work.

Any ideas on how to make more consistent in acquiring a location using cell sites?

[NOTiFYPiNPOiNT]

I use;

if (location != null && location.isValid()) {

To add the Latitude & Longitude to the string I send back to the server. If this data is null then when it is processed by my EJB on the server it uses the Cell ID & LAC code to get the Latitude & Longitude.

Ideally you (we) should be using;

public void providerStateChanged(final LocationProvider provider, final int newState) {

There is a bug and this method is never called, well at least not on the Bold 9700. It has been raised on the BB bug tracker.  See my post;

http://supportforums.blackberry.com/t5/Java-Development/locationProvider-getLocation-re-creating/m-p...

If this is effecting you perhaps you can vote for it to be fixed? The more the merrier!