Clear MKMapView's cache of tiles?

Question

I'm working on an iPhone game that uses an MKMapView as the playfield. After only a couple of minutes of play the app inevitably starts to get sluggish and eventually crashes due to low memory. After digging around the culprit seems to be that the map view constantly demands more memory. The game requires a lot of zooming and panning of the map so I can only assume that the map's cache of tiles just keeps growing until it runs out of memory. Is there any way to force the map view to flush it's cache of tiles or contain it's memory consumption?

Answer 1

Are you setting the reuse identifier on your annotation views? (This means the system can detach those views and only keep a small number of views in memory at once. It also increases scrolling performance, because scrolling will reuse the detached views.)

Use this method to get an annotation view to be reused:

 - (MKAnnotationView *)dequeueReusableAnnotationViewWithIdentifier:(NSString *)identifier