[TIMOB-1122] Geolocation listener fires repeatedly

Description

Comments

1. Curtis Olson 2011-04-15

   Here is the code from app.js that requests location. It is very close to the KitchenSink code.

      try {
          Ti.API.debug('Titanium.Geolocation.locationServicesEnabled: ' + Titanium.Geolocation.locationServicesEnabled);
          if (Titanium.Geolocation.locationServicesEnabled == false) {
              Titanium.UI.createAlertDialog({
                  title: 'Warning',
                  message: 'Your device has geolocation turned off. Please turn it on now.'
              }).show();
          }
          else {
              Ti.API.debug('Location services are available');
              //
              //  SET ACCURACY
              //
              Titanium.Geolocation.accuracy = Titanium.Geolocation.ACCURACY_BEST;
              //
              //  SET DISTANCE FILTER.  THIS DICTATES HOW OFTEN AN EVENT FIRES BASED ON THE DISTANCE THE DEVICE MOVES
              //  THIS VALUE IS IN METERS
              //
              Titanium.Geolocation.distanceFilter = 10;
              //
              // GET CURRENT POSITION - THIS FIRES ONCE
              //
              var myLongitude;
              var myLatitude;
              var myAltitude;
              var myHeading;
              var myAccuracy;
              var mySpeed;
              var myGeoTimestamp;
              var myAltitudeAccuracy;
              Titanium.Geolocation.getCurrentPosition(function(e){        
                  if (e.error) {
                      Ti.API.error('Geolocation Error');
                      Ti.API.error('error:' + JSON.stringify(e.error));
                      return;
                  };
                  // get values from geolocation call
                  myLatitude = e.coords.latitude;
                  Titanium.App.Properties.setDouble('myLatitude', myLatitude);
                  myLongitude = e.coords.longitude;
                  Titanium.App.Properties.setDouble('myLongitude', myLongitude);
                  myAltitude = e.coords.altitude;
                  myHeading = e.coords.heading;
                  myAccuracy = e.coords.accuracy;
                  mySpeed = e.coords.speed;
                  myGeoTimestamp = e.coords.timestamp;
                  myAltitudeAccuracy = e.coords.altitudeAccuracy;
                  showVariables('Got Geolocation info');
              });
              //
              // EVENT LISTENER FOR GEO EVENTS - THIS WILL FIRE REPEATEDLY (BASED ON DISTANCE FILTER)
              //
              Titanium.Geolocation.addEventListener('location', function(e){
                  if (e.error) {
                      Ti.API.error('Geolocation Error');
                      Ti.API.error('error:' + JSON.stringify(e.error));
                      return;
                  };
                  
                  // get values from geolocation call
                  myLatitude = e.coords.latitude;
                  Titanium.App.Properties.setDouble('myLatitude', myLatitude);
                  myLongitude = e.coords.longitude;
                  Titanium.App.Properties.setDouble('myLongitude', myLongitude);
                  myAltitude = e.coords.altitude;
                  myHeading = e.coords.heading;
                  myAccuracy = e.coords.accuracy;
                  mySpeed = e.coords.speed;
                  myGeoTimestamp = e.coords.timestamp;
                  myAltitudeAccuracy = e.coords.altitudeAccuracy;
                  
                  geoCount = geoCount + 1;
                  Ti.API.info('***********  Geo: ' + geoCount + ' ' + myLatitude + '/' + myLongitude + ' ');
                  Titanium.Geolocation.distanceFilter = 100; // changed after first location event 
              });
          };
      }
      catch(err) {
          Titanium.UI.createAlertDialog({
              title: 'Geolocation Error',
              message: err
          }).show();  
      };
      

2. Udi 2011-04-15

   I'm seeing the same behavior. It doesn't make any sense.

3. Clifton Labrum 2011-04-15

   I'm see this problem as well.

   When I test the code in the KitchenSink, I can't get the position to update based on a position change (according to the distance filter). Only the initial position is acquired, and no subsequent positions are acquired. The distance filter seems inoperable.

   The only way I've managed to get working GPS functionality is to call getCurrentPosition on the location event like this:

      Ti.Geolocation.addEventListener('location', getPosition);
      
      function getPosition(e) {
          
          //Watch for errors
          if(e.error){ return; }
      
          Ti.Geolocation.accuracy = Ti.Geolocation.ACCURACY_BEST;
          Ti.Geolocation.distanceFilter = 100;            
        
          Ti.Geolocation.getCurrentPosition(function(e){
              if(e.error){ return; }
              
              //Get the GPS goods
              var longitude = e.coords.longitude;
              var latitude = e.coords.latitude;
              var altitude = e.coords.altitude;
              var accuracy = e.coords.accuracy;
              var timestamp = e.coords.timestamp;
          });
      }
      

   So I'm basically getting the initial position over and over again using the location event. It feels wrong, but it's the only thing I've been able to figure out.

4. Norm 2011-04-15

   Having the same problem with the kitchen sink code, it only seems to update the first time then hangs. Although, after opening the google maps app and allowing the GPS to sync and pulse, closing google maps, then opening the kitchen sink app again it seems to work properly and location updates flow in and regular intervals. Any ideas!?

5. Taazza 2011-04-15

   We are seeing the same problem that norm is seeing.

   Later location updates seem to fire up even when the location doesnt change. Kitchensink example doesnt work as coded. Let us know if you need more info.

6. Stephen Tramer 2011-04-15

   Looks like this is a pressing issue.

7. Stephen Tramer 2011-05-04 "Fixed" by 89ba1a4. Issue was that we had a feature which covers this issue, but it was not documented.
8. Steve 2011-05-09 @Stephen Tramer, Where can we find the documentation?
9. Stephen Tramer 2011-05-09 In the apidocs, which are not published until release. You can always view the specific changes made to the documentation formatting files: https://github.com/appcelerator/titanium_mobile/commit/89ba1a4b9f450909cc58c67cdf0d8669f388d9d7#diff-0
10. Lee Morris 2017-03-02 Closed as invalid.

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