SKPOITrackerManager not working as excepted

问题:

I am using SKPOITrackerManager to track self-defined trackable POIs in navigation mode. The arraylist of SKTrackablePOI objects has many elements which are placed near my route. But only one of them is tracked by onReceivedPOIs(). This method only returns a one-element-list. But it is called 5 to 10 times for exactly one POI. I am sorry that I can not post my complete code here due to project agreement. But here I can show you my settings in an implementation of the SKPOITrackerListener interface:

public void startPOITracking() {
    poiTrackerManager = new SKPOITrackerManager(this);
    SKTrackablePOIRule skTrackablePOIRule = new SKTrackablePOIRule();
    skTrackablePOIRule.setAerialDistance(15000);
    skTrackablePOIRule.setRouteDistance(15000);
    skTrackablePOIRule.setNumberOfTurns(15000);
    skTrackablePOIRule.setMaxGPSAccuracy(15000);
    skTrackablePOIRule.setEliminateIfUTurn(false);
    skTrackablePOIRule.setMinSpeedIgnoreDistanceAfterTurn(12000);
    skTrackablePOIRule.setMaxDistanceAfterTurn(150000);
    poiTrackerManager.startPOITrackerWithRadius(100, 0.5);
    poiTrackerManager.setRuleForPOIType(SKTrackablePOIType.INVALID, skTrackablePOIRule);
    poiTrackerManager.addWarningRulesforPoiType(SKTrackablePOIType.INVALID);
}

I have set the limitions to very high values within SKTrackablePOIRule and still a get only one POI. I can even comment out the line with poiTrackerManager.setRuleForPOIType(SKTrackablePOIType.INVALID, skTrackablePOIRule); and I still receive only one single POI. Maybe someone can help to understand my problem.

回答1:

Here is something I used in the past:

poiTrackingManager = new SKPOITrackerManager(this);
SKTrackablePOIRule rule = new SKTrackablePOIRule();
rule.setAerialDistance(5000); // this would be our main constraint, stating that all the POIs with 5000m, aerial distance should be detected
rule.setNumberOfTurns(100); // this has to be increased – otherwise some points will be disconsidered
rule.setRouteDistance(10000);//this has to be increased as the real road route will be longer than the aerial distance
rule.setMinSpeedIgnoreDistanceAfterTurn(20); //decrease this to evaluate all candidates
rule.setMaxDistanceAfterTurn(10000); //increase this to make sure we don't exclude any candidates
rule.setEliminateIfUTurn(false); // setting this to true (default) excludes points that require us to make an U-turn to get to them 
rule.setPlayAudioWarning(false);

Note: I'm not certain what are the max/min values for these parameters as I've seen some issues when they are too high (they do affect the routing algorithm, more precissely how the road graph is explored so this could explain why at high values it might malfunction) - I would say that you should start with conservative values and then gradually increase them

For startPOITrackerWithRadius I would use different values as if you set the radius to 100 (meters) this would greatly reduce the number of POIs that the SDK is able to analyze (even if the rules are good, the POIs might not be analyzed as they don't fall in the "radius" (aerial distance) around your current position) :

poiTrackingManager.startPOITrackerWithRadius(1500, 0.5);

Also see http://sdkblog.skobbler.com/detecting-tracking-pois-in-your-way/ for more insights on how the POITraker works