How to remove cache of cllocation?

问题:

I am developing an iPhone app which is a location aware app . Currentlly the app is working fine except the caching of previous location . The first time I start the application location manager fetches the current location and then I display nearby things based on the current location .

But from the next it uses previously fetched location and until I restart the phone it will fetch the same location . So up to this point I am clear that the location manager caches the location .

So my question is how to remove this cache and force the location manager to fetch a new location thanks

回答1:

Actually I don't think you can : it's up to you (in your CLLocationManagerDelegate instance) to filter the position you receive based on its timestamp (to ensure that the position you work on is a recent one, not a cached one).

-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{
    NSDate *eventDate = newLocation.timestamp; 
    NSTimeInterval howRecent = [eventDate timeIntervalSinceNow];
    //Is the event recent and accurate enough ?
    if (abs(howRecent) < SECS_OLD_MAX) {
        //WORK WITH IT !
    }
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