Customize user location tint on iOS - ios

Question

I'm trying to change the color of the user location, as it is done in the "find my friends" app by Apple (see attached screenshot).
Note that I'm using the MapBox SDK, and I currently have the following method:
- (RMMapLayer *)mapView:(RMMapView *)mapView layerForAnnotation:(RMAnnotation *)annotation
{
if (annotation.isUserLocationAnnotation)
return nil;
}
I also looked into this thread to have an idea about how I should do something similar, but didn't find the same code for user location. Did Apple use a static PNG picture for Find my friends? Will I lose the adaptive circle around the position by changing it to another color (if that's even possible)?
UPDATE
As #Incanus said in his reply, in my -[RMMapViewDelegate mapView:layerForAnnotation:] callback method, I should get three calls corresponding to isUserLocationAnnotation = YES -- the dot, the accuracy circle, and the pulsing halo.
I only get one, and I don't get why.
Also, I tried to customise the annotation when the tracking mode changes, here's what I did:
if (self.mMapView.userTrackingMode == RMUserTrackingModeNone)
{
for (RMAnnotation *annotation in self.mMapView.annotations) {
if (annotation.isUserLocationAnnotation) {
if ([annotation.annotationType isEqualToString:#"RMAccuracyCircleAnnotation"]) {
[(RMCircle*)annotation.layer setFillColor:[[UIColor redColor] colorWithAlphaComponent:0.6]];
[(RMCircle*)annotation.layer removeAllAnimations];
}
}
}
[self enableBouncingOnLayer:self.mMapView.userLocation.layer];
}
else
{
[self.mMapView.userLocation.layer removeAnimationForKey:#"animateScale"];
}
So far so good, I get the blue accuracy circle to turn red and stop changing size.
The problem is, the MapBox framework will still update it, so it will go back to normal.
What's interesting is, using this method, I do have 3 annotation with isUserLocationAnnotation set to YES, but I only get one callback.
Any help appreciated.

Answer 1

In Swift 3,
mapView.tintColor = .red
Wonderfully straight forward now.

Answer 2

For the MapBox SDK, you can access the actual blue dot inside of the resources bundle and create a tinted version, either on the fly with Core Graphics or ahead of time as another resource in your bundle.
In Find My Friends, the dot is still blue -- they are actually just using an altered copy for other annotations. You can do the same.
You might also be interested in https://github.com/0xced/UIKit-Artwork-Extractor specifically for pulling resources out of the Find My Friends app, which is actually what we used on the MapKit framework to get the blue dot for the MapBox SDK ;-)

Answer 3

As Incanus pointed it out, I'm using the layerForAnnotation: method to customize my user annotation.
I then created this method to force an update of the layer, so that it can be drawn again.
- (void)refreshUserAnnotation {
[mUserAnnotation setLayer: [self mapView:mMapView layerForAnnotation:mUserAnnotation]];
}