Check if user location is visible on map iphone

问题

I want to hide or show a UIButton weather user's current location is visible on map. While testing the code xcode I can see meassage "User location view is NOT visible but should be. Showing...." on console in "didUpdateLocation" method if users location is not visible on map. How can I use this message to generate events in my case to hide or show a UIButton? Thanks for any help in advance.

回答1:

If you want to know whether the user location is contained in the currently displayed map region, you can check the userLocationVisible property in the regionDidChangeAnimated delegate method:

- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated
{
    someButton.hidden = !mapView.userLocationVisible;
}

If you just want to know whether the user location currently has a value (whether it's visible or not and whether showsUserLocation is on or not), then:

if (mapView.userLocation.location == nil)
    NSLog(@"user location not obtained yet");
else
    NSLog(@"user location available (may or may not be currently visible)"):

回答2:

There is property called userLocationVisible.

In Apple Docs

A Boolean value indicating whether the device’s current location is visible in the map view. (read-only)

回答3:

if user location is not visible you does not get current lat,long . put the condition if lat ,long == 0. then button hide or show. it work on only device(gps)

来源：https://stackoverflow.com/questions/7320101/check-if-user-location-is-visible-on-map-iphone

标签

iphone

mapkit

userlocation