I'm trying to get user location and display it in mapView with following code in iOS6:
- (void) locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations{
if (locations.count>0) {
for (CLLocation *location in locations) {
[locationList addObject:location];
if (location != nil) {
// Zoom to the current user location.
MKCoordinateRegion userLocation =[mapView regionThatFits: MKCoordinateRegionMakeWithDistance(location.coordinate, 150.0, 150.0)];
[mapView setRegion:userLocation animated:YES];
NSLog(#"%f,%f", mapView.centerCoordinate.latitude,mapView.centerCoordinate.longitude);
NSLog(#"%f,%f", mapView.region.span.latitudeDelta,mapView.region.span.longitudeDelta);
}
}
}
}
but after location updated,[mapView setRegion:userLocation animated:YES] does not make any change to region of mapView, but the user location can be display as a blue dot. the NSLog prints like this:
nan,nan
0.000000,360.000000
Which means nothing changed. I checked most questions related map, they just call this method and get location display in the center of map.
I want to know why how can I put user location to the map center.
You could just turn on the MKMapView tracking mode
[mapView setTrackingMode:MKMapViewTrackingModeFollowsUser];
You can try this:
mMapView.showsUserLocation = YES;
Related
I am just looking at mapKit and decided to make a quick button to display my current location, however when I press the button my latitude/longitude always display as [0.000000] [0.000000].
The mapView is loaded as I can see the map on the simulator before I press the button. Previously I have done this by using coreLocation.framework and using CLLocationManager and asking for the device location that way. I am just curious why this way is not working correctly, would I be better doing this via CLLocationManager?
-(IBAction)findMePressed {
MKUserLocation *myLocation = [myMapView userLocation];
CLLocationCoordinate2D coord = [[myLocation location] coordinate];
[myMapView setCenterCoordinate:coord animated:YES];
NSLog(#"findMePressed ...[%f][%f]", coord.latitude, coord.longitude);
}
EDIT: Added ...
-(IBAction)findMePressed {
MKUserLocation *myLocation = [myMapView userLocation];
CLLocationCoordinate2D coord = [[myLocation location] coordinate];
MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(coord, 350, 350);
[myMapView setRegion:region animated:YES];
}
-(void)viewDidLoad {
[super viewDidLoad];
[myMapView setShowsUserLocation:YES];
}
Gary.
Either the userLocation is not visible on the map (see the userLocationVisible property) or there is some problem setting up the myMapView property and it's nil (i.e. not connected in interface builder)
[...] as I can see the map on the simulator [...]
Test it on the device. By default, on the simulator, the coordinates you get back are Apple's headquarters. Cf. doc.
See this other SO question for workarounds and useful utilities : Testing CoreLocation on iPhone Simulator
I'm trying to animate a radar image on an MKMapView. I have separate images for different times, and I have successfully set an image as an overlay on top of the MKMapView. My problem is when I try to show these different images in a sequence one after each other. I tried a method of adding and removing overlays, but the system does not handle it well at all, with flickering of overlays, and some overlays not being removed, and overall, its not worth it.
Could anyone help me find a way to show multiple images (like an animated gif) on top of a MapView in a way that is smooth and fast?
Here's my code to overlay the image:
- (id)initWithImageData:(NSData*)imageData withLowerLeftCoordinate:(CLLocationCoordinate2D)lowerLeftCoordinate withUpperRightCoordinate:(CLLocationCoordinate2D)upperRightCoordinate {
self.radarData = imageData;
MKMapPoint lowerLeft = MKMapPointForCoordinate(lowerLeftCoordinate);
MKMapPoint upperRight = MKMapPointForCoordinate(upperRightCoordinate);
mapRect = MKMapRectMake(lowerLeft.x, upperRight.y, upperRight.x - lowerLeft.x, lowerLeft.y - upperRight.y);
return self;
}
- (CLLocationCoordinate2D)coordinate
{
return MKCoordinateForMapPoint(MKMapPointMake(MKMapRectGetMidX(mapRect), MKMapRectGetMidY(mapRect)));
}
- (MKMapRect)boundingMapRect
{
return mapRect;
}
and here's how I'm setting it up on the MapView:
- (void)drawMapRect:(MKMapRect)mapRect
zoomScale:(MKZoomScale)zoomScale
inContext:(CGContextRef)ctx
{
MapOverlay *mapOverlay = (MapOverlay *)self.overlay;
image = [[UIImage alloc] initWithData:mapOverlay.radarData];
MKMapRect theMapRect = [self.overlay boundingMapRect];
CGRect theRect = [self rectForMapRect:theMapRect];
#try {
UIGraphicsBeginImageContext(image.size);
UIGraphicsPushContext(ctx);
[image drawInRect:theRect blendMode:kCGBlendModeNormal alpha:0.5];
UIGraphicsPopContext();
UIGraphicsEndImageContext();
}
#catch (NSException *exception) {
NSLog(#"Caught an exception while drawing radar on map - %#",[exception description]);
}
#finally {
}
}
and here's where I'm adding the overlay:
- (void)mapRadar {
AppDelegate *appDelegate = (AppDelegate *)[[UIApplication sharedApplication] delegate];
self.mapOverlay = [[MapOverlay alloc] initWithImageData:appDelegate.image withLowerLeftCoordinate:CLLocationCoordinate2DMake(appDelegate.south, appDelegate.west) withUpperRightCoordinate:CLLocationCoordinate2DMake(appDelegate.north, appDelegate.east)];
[self.mapView addOverlay:self.mapOverlay];
[self.mapView setNeedsDisplay];
self.mapView.showsUserLocation = YES;
MKMapPoint lowerLeft2 = MKMapPointForCoordinate(CLLocationCoordinate2DMake(appDelegate.south2, appDelegate.west2) );
MKMapPoint upperRight2 = MKMapPointForCoordinate(CLLocationCoordinate2DMake(appDelegate.north2, appDelegate.east2));
MKMapRect localMapRect = MKMapRectMake(lowerLeft2.x, upperRight2.y, upperRight2.x - lowerLeft2.x, lowerLeft2.y - upperRight2.y);
[self.mapView setVisibleMapRect:localMapRect animated:YES];
}
#pragma Mark - MKOverlayDelgateMethods
-(MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id)overlay{
if([overlay isKindOfClass:[MapOverlay class]]) {
MapOverlay *mapOverlay = overlay;
self.mapOverlayView = [[MapOverlayView alloc] initWithOverlay:mapOverlay];
}
return self.mapOverlayView;
}
Does anyone have an idea or a solution where I can show a sequence of images on an MKMapView smoothly? At this point, I'm desperate for solutions and can't find it anywhere else, so anything would help me, thanks!
Using Lefteris' suggestion, you can just use UIImageView with animationImages. The animation should be smooth provided your overlay images are properly sized for the screen.
To pass touches through to the map view below, you can create a new UIView subclass with a (weak) reference to the map view. Override the touch event methods (touchesBegan:withEvent:, touchesMoved:withEvent:, etc) to forward to the map view, like so:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.mapView touchesBegan:touches withEvent:event];
}
This way the user can still interact with the view below.
You may run into problems when the user tries to zoom, as it will be difficult if not impossible to scale all your animation frames in real-time. You should look into using CATiledLayer instead.
I need to draw the current user annotation (the blue dot) on top of all other annotations. Right now it is getting drawn underneath my other annotations and getting hidden. I'd like to adjust the z-index of this annotation view (the blue dot) and bring it to the top, does anyone know how?
Update:
So I can now get a handle on the MKUserLocationView, but how do I bring it forward?
- (void) mapView:(MKMapView *)aMapView didAddAnnotationViews:(NSArray *)views {
for (MKAnnotationView *view in views) {
if ([[view annotation] isKindOfClass:[MKUserLocation class]]) {
// How do I bring this view to the front of all other annotations?
// [???? bringSubviewToFront:????];
}
}
}
Finally got it to work using the code listed below thanks to the help from Paul Tiarks. The problem I ran into is that the MKUserLocation annotation gets added to the map first before any others, so when you add the other annotations their order appears to be random and would still end up on top of the MKUserLocation annotation. To fix this I had to move all the other annotations to the back as well as move the MKUserLocation annotation to the front.
- (void) mapView:(MKMapView *)aMapView didAddAnnotationViews:(NSArray *)views
{
for (MKAnnotationView *view in views)
{
if ([[view annotation] isKindOfClass:[MKUserLocation class]])
{
[[view superview] bringSubviewToFront:view];
}
else
{
[[view superview] sendSubviewToBack:view];
}
}
}
Update: You may want to add the code below to ensure the blue dot is drawn on top when scrolling it off the viewable area of the map.
- (void)mapView:(MKMapView *)mapView regionDidChangeAnimated:(BOOL)animated
{
for (NSObject *annotation in [mapView annotations])
{
if ([annotation isKindOfClass:[MKUserLocation class]])
{
NSLog(#"Bring blue location dot to front");
MKAnnotationView *view = [mapView viewForAnnotation:(MKUserLocation *)annotation];
[[view superview] bringSubviewToFront:view];
}
}
}
Another solution:
setup annotation view layer's zPosition (annotationView.layer.zPosition) in:
- (void)mapView:(MKMapView *)mapView didAddAnnotationViews:(NSArray *)views;
The official answer to that thread is wrong... using zPosition is indeed the best approach and fastest vs using regionDidChangeAnimated...
else you would suffer big performance impact with many annotations on map (as every change of frame would rescan all annotations). and been testing it...
so when creating the view of the annotation (or in didAddAnnotationViews) set :
self.layer.zPosition = -1; (below all others)
and as pointed out by yuf:
This makes the pin cover callouts from other pins – yuf Dec 5 '13 at 20:25
i.e. the annotation view will appear below other pins.
to fix, simply reput the zPosition to 0 when you have a selection
-(void) mapView:(MKMapView*)mapView didSelectAnnotationView:(MKAnnotationView*)view {
if ([view isKindOfClass:[MyCustomAnnotationView class]])
view.layer.zPosition = 0;
...
}
-(void) mapView:(MKMapView*)mapView didDeselectAnnotationView:(MKAnnotationView*)view {
if ([view isKindOfClass:[MyCustomAnnotationView class]])
view.layer.zPosition = -1;
...
}
Update for iOS 14
I know it's an old post, but the question is still applicable and you end up here when typing it into your favorite search engine.
Starting with iOS 14, Apple introduced a zPriority property to MKAnnotationView. You can use it to set up the z-index for your annotations using predefined constants or floats.
Also, Apple made it possible to finally create the view for the user location on our own and provided MKUserLocationView as a subclass of MKAnnotationView.
From the documentation for MKUserLocationView:
If you want to specify additional configuration, such as zPriority,
create this annotation view directly. To display the annotation view,
return the instance from mapView(_:viewFor:).
The following code snippet shows how this can be done (add the code to your MKMapViewDelegate):
func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
// Alter the MKUserLocationView (iOS 14+)
if #available(iOS 14.0, *), annotation is MKUserLocation {
// Try to reuse the existing view that we create below
let reuseIdentifier = "userLocation"
if let existingView = mapView.dequeueReusableAnnotationView(withIdentifier: reuseIdentifier) {
return existingView
}
let view = MKUserLocationView(annotation: annotation, reuseIdentifier: reuseIdentifier)
view.zPriority = .max // Show user location above other annotations
view.isEnabled = false // Ignore touch events and do not show callout
return view
}
// Create views for other annotations or return nil to use the default representation
return nil
}
Note that per default, the user location annotation shows a callout when tapping on it. Now that the user location overlays your other annotations, you'd probably want to disable this, which is done in the code by setting .isEnabled to false.
Just use the .layer.anchorPointZ property.
Example:
func mapView(_ mapView: MKMapView, didAdd views: [MKAnnotationView]) {
views.forEach {
if let _ = $0.annotation as? MKUserLocation {
$0.layer.anchorPointZ = 0
} else {
$0.layer.anchorPointZ = 1
}
}
}
Here is there reference https://developer.apple.com/documentation/quartzcore/calayer/1410796-anchorpointz
Try, getting a reference to the user location annotation (perhaps in mapView: didAddAnnotationViews:) and then bring that view to the front of the mapView after all of your annotations have been added.
Swift 3:
internal func mapView(_ mapView: MKMapView, didAdd views: [MKAnnotationView]) {
for annotationView in views {
if annotationView.annotation is MKUserLocation {
annotationView.bringSubview(toFront: view)
return
}
annotationView.sendSubview(toBack: view)
}
}
Here is a way to do it using predicates. I think it should be faster
NSPredicate *userLocationPredicate = [NSPredicate predicateWithFormat:#"class == %#", [MKUserLocation class]];
NSArray* userLocation = [[self.mapView annotations] filteredArrayUsingPredicate:userLocationPredicate];
if([userLocation count]) {
NSLog(#"Bring blue location dot to front");
MKAnnotationView *view = [self.mapView viewForAnnotation:(MKUserLocation *)[userLocation objectAtIndex:0]];
[[view superview] bringSubviewToFront:view];
}
Using Underscore.m
_.array(mapView.annotations).
filter(^ BOOL (id<MKAnnotation> annotation) { return [annotation
isKindOfClass:[MKUserLocation class]]; })
.each(^ (id<MKAnnotation> annotation) { [[[mapView
viewForAnnotation:annotation] superview] bringSubviewToFront:[mapView
viewForAnnotation:annotation]]; });
I have been trying to centre the map view on the users location. This should also update as and when a change in location is registered. The issue I'm having is upon loading the app I can't get hold of the current latitude and longitude to apply the centring & zooming.
These are the key bits of code I have so far...
- (void)viewDidLoad
{
self.locationManager = [[CLLocationManager alloc] init];
locationManager.delegate = self;
locationManager.desiredAccuracy = kCLLocationAccuracyBest;
[locationManager startUpdatingLocation];
[self updateMapZoomLocation:locationManager.location];
[super viewDidLoad];
}
The idea being that it should create an instance of the location manager, then start updating the location. Finally it should run the function I wrote to update the map view accordingly...
- (void)updateMapZoomLocation:(CLLocation *)newLocation
{
MKCoordinateRegion region;
region.center.latitude = newLocation.coordinate.latitude;
region.center.longitude = newLocation.coordinate.longitude;
region.span.latitudeDelta = 0.1;
region.span.longitudeDelta = 0.1;
[map setRegion:region animated:YES];
}
However this doesn't seem to happen. The app builds and runs ok, but all that gets displayed is a black screen - it's as if the coordinates don't exist?!
I also have a delegate method that deals with any updates by calling the function above...
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation
{
[self updateMapZoomLocation:newLocation];
}
I have tried looking at several of the other similar questions that have been asked & answered previously however I still can't seem to find the solution I'm after.
Any help on this would be really appreciated; I've spent hours and hours trawling the internet in search of help and solutions.
ps. 'map' is the mapView.
You want to use the MKMapViewDelegate callback so you only zoom in once the location is actually known:
Here's some swift code to handle that:
var alreadyZoomedIn = false
func mapView(mapView: MKMapView!, didUpdateUserLocation userLocation: MKUserLocation!) {
if(!alreadyZoomedIn) {
self.zoomInOnCurrentLocation()
alreadyZoomedIn = true
}
}
func zoomInOnCurrentLocation() {
var userCoordinate = mapView?.userLocation.coordinate
var longitudeDeltaDegrees : CLLocationDegrees = 0.03
var latitudeDeltaDegrees : CLLocationDegrees = 0.03
var userSpan = MKCoordinateSpanMake(latitudeDeltaDegrees, longitudeDeltaDegrees)
var userRegion = MKCoordinateRegionMake(userCoordinate!, userSpan)
mapView?.setRegion(userRegion, animated: true)
}
You shouldn't call updateMapZoomLocation during your viewDidLoad function because the location manager has not yet go a location. If/when it does it'll call the delegate function when it's ready. Until then your map won't know where to center. You could try zooming as far out as it goes, or remembering where it was last looking before the app was shutdown.
I am using map kit and showing customized annotation view. One is carImage and the another one is userImage(as current location of user). Now I want to show current user location default which is provided by map kit.but unable to show it. How do I show blue circle+my car in map kit?
To show the user location, set the following property to true on the map view object
mapView.showsUserLocation = YES;
To display a custom annotation, set image property on the map view annotation
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
// check for nil annotation, dequeue / reuse annotation
// to avoid over riding the user location default image ( blue dot )
if ( mapView.UserLocation == annotation ) {
return nil; // display default image
}
MKAnnotationView* pin = (MKAnnotationView*)
[mapView dequeueReusableAnnotationViewWithIdentifier: PIN_RECYCLE_ID];
if ( pin == nil ) {
pin = [(MKAnnotationView*) [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier: PIN_RECYCLE_ID] autorelease] ;
pin.canShowCallout = YES;
}
else {
[pin setAnnotation: annotation];
}
pin.image = [UIImage imageNamed:#"car-image.png"];
return pin;
}