mapView:viewForAnnotation: not always called - ios

I am just starting out wit MKMapKit and call outs. In particular, I have started to use mapView: viewForAnnotation: and a right accessory button. My problem is that the method only get called for newly added pins but not for those previously added to the map view. The call out opens but without a right accessory. Should this method be called for all pins?
-(MKAnnotationView*)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation{
static NSString *resuseId = #"WaypointMapViewVC";
MKAnnotationView *view =[mapView dequeueReusableAnnotationViewWithIdentifier:resuseId];
if (!view){
view = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:resuseId];
view.canShowCallout=YES;
UIButton *rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
view.rightCalloutAccessoryView=rightButton;
} else {
view.annotation=annotation;
}
return view;
}
Am I doing something wrong here?

Related

Wrong presentation of pins in MapKit (color and annotation) [duplicate]

I am trying to make a map, where I can see my current location, and see what the street is called.
so far, I am able to put a pin on my map, but for some reason, I am not getting the callout.
and I have put a NSLog in my viewForAnnotation method, but it is not being called, so i wasn't able to test it.
can someone help me?
-(void)lat:(float)lat lon:(float)lon
{
CLLocationCoordinate2D location;
location.latitude = lat;
location.longitude = lon;
NSLog(#"Latitude: %f, Longitude: %f",location.latitude, location.longitude);
//One location is obtained.. just zoom to that location
MKCoordinateRegion region;
region.center=location;
//Set Zoom level using Span
MKCoordinateSpan span;
span.latitudeDelta=.005f;
span.longitudeDelta=.005f;
region.span=span;
[map setRegion:region animated:TRUE];
//MKReverseGeocoder *geocoder=[[MKReverseGeocoder alloc] initWithCoordinate:location];
//geocoder.delegate=self;
//[geocoder start];
if (cPlacemark != nil) {
[map removeAnnotation:cPlacemark];
}
cPlacemark=[[CustomPlacemark alloc] initWithCoordinate:location];
cPlacemark.title = mPlacemark.thoroughfare;
cPlacemark.subtitle = mPlacemark.locality;
[map addAnnotation:cPlacemark];
[cPlacemark release];
[mLocationManager stopUpdatingLocation];
}
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation {
if ([annotation isKindOfClass:[MKUserLocation class]])
return nil;
// try to dequeue an existing pin view first
if ([annotation isKindOfClass:[CustomPlacemark class]]){
MKPinAnnotationView *pinView=(MKPinAnnotationView *)[map dequeueReusableAnnotationViewWithIdentifier:#"customIdentifier"];
if (!pinView)
{
// if an existing pin view was not available, create one
MKPinAnnotationView* cPinAnnoView = [[[MKPinAnnotationView alloc]
initWithAnnotation:annotation reuseIdentifier:#"customIdentifier"] autorelease];
cPinAnnoView.pinColor = MKPinAnnotationColorPurple;
cPinAnnoView.animatesDrop = YES;
cPinAnnoView.canShowCallout = YES;
// Add button
UIButton *leftButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[leftButton addTarget:self action:#selector(annotationViewClick:) forControlEvents:UIControlEventTouchUpInside];
cPinAnnoView.leftCalloutAccessoryView = leftButton;
} else
{
pinView.annotation = annotation;
}
return pinView;
}
return nil;
}
Right now I have customized my viewForAnnotation to be like this.
But I still can't get a callout from my pin and the pin remains red.
But it should be purple of nothing at all
I had the same problem which was not setting the MapView delegate to the File Owner.
Open your nib
Right click on the MapView
Drag the delegate to the File's Owner
I had the same problem, as you mentioned. The delegate had been set to ViewController, but the viewForAnnotation selector was not being called. After some checks, I realized if you do not call addAnotation in the main thread, mapView would not call viewForAnnotation, so following update resolved my problem:
Before:
[_mMapView addAnnotation:marker];
After:
dispatch_async(dispatch_get_main_queue(), ^{
[_mMapView addAnnotation:marker];
});
In order to get the viewForAnnotation to be called, add mapView.delegate=self; to e.g. the viewDidLoad method:
- (void)viewDidLoad {
[super viewDidLoad];
mapView.delegate=self;
}
Could it be that your annotation has been added outside the current view area of the MKMapView?
For storyboard, Ctl drag the MKMapView to the orange circle on the bottom bar of ViewController, and select delegate.
This will solve the problem.
As vatrif mentioned in the comments, you must set your delegate BEFORE adding annotations to your MKMapView object.
Others have already explained, odds are high you have not connected your mapview delegate to your controller. Its the first thing to check
i have been working in ios 9 Mapview related app and I experienced the same problem.
somehow I solved my problem, in my case im resizing the mapview.
I added delegate after i resize the mapview. it works now perfectly.!
After having set the delegate for the mapview if still the viewforannotation not getting called then this is something which you have missed - set the self.mapView.showsUserLocation to YES, in interface builder you can tick the shows userLocation option in attributes inspector.

Custom MKAnnotationView expandable without callout

I want to create custom MKAnnotationView (with image) without a callout, but expandable after touch. Here is what i have in mind:
1) First the MKAnnotation looks like this:
2) Then after tap on it this should expand and looks like this:
I've started with customing MKAnnotationView and have a class:
#interface CustomPinAnnotation : NSObject <MKAnnotation>
The class have method:
-(MKAnnotationView*)annotationView {
MKAnnotationView *annotationView = [[MKAnnotationView alloc] initWithAnnotation:self reuseIdentifier:#"AnnotationIdentifier"];
annotationView.enabled = YES;
annotationView.image = [[UIImage imageNamed:#"star"] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
return annotationView;
}
And what i try to do is set a customView as a subview to the MKAnnotationView, but when i don't set The image it will not responding (this is pretty logical after i've think about it), but got the feeling that I'm doing something very nasty here, and should be a way to override MKAnnotationView somehow.
-(MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
enemyAnnotationView.image = [UIImage imageNamed:#"firstImage.png"];
}
-(void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view
{
enemyAnnotationView.image = [UIImage imageNamed:#"SecondImage.png"];
}
Try like this first method is for the View for annotation that time your first image will be appears,
Second method will run when user select annotation

Force MKMapView viewForAnnotation to update

So I have a MKMapView with all my pins added, and the colour of the pin is dependent on whether a value is set for that pin. When I first load the app, viewForAnnotation is called and the colours are set accordingly. However, when I update the pin's details (such as location, title, etc...) I also update the pinColour to find it doesn't update. It looks like viewForAnnotation isn't called again after the initial add.
I have read many questions similar to this and I can confirm that mapView.delegate = self;
Here is my viewForAnnotation code:
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(MapAnnotation *)annotation
{
if([annotation class] == MKUserLocation.class)
return nil;
NSString *pinIdentifier = annotation.identifier; // This is a unique string for each pin and is getting populated every time!
MKPinAnnotationView *annotationView = (MKPinAnnotationView *) [mapView dequeueReusableAnnotationViewWithIdentifier:pinIdentifier];
if(annotationView == nil)
annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:pinIdentifier];
else
annotationView.annotation = annotation; // Never had this line fire...
annotationView.canShowCallout = YES;
annotationView.animatesDrop = NO;
annotationView.enabled = YES;
annotationView.tag = annotation.counter;
if(annotation.pinColour == Stopped) // from enum
annotationView.pinColor = MKPinAnnotationColorRed;
else
annotationView.pinColor = MKPinAnnotationColorGreen;
UIButton *infoButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[infoButton addTarget:self action:#selector(mapCalloutButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
infoButton.tag = annotation.counter;
annotationView.rightCalloutAccessoryView = infoButton;
return annotationView;
}
Here is the code where I add the pin:
CLLocationCoordinate2D annotationCoord;
annotationCoord.latitude = latestPosition.latitude;
annotationCoord.longitude = latestPosition.longitude;
MapAnnotation *annotation = [[MapAnnotation alloc] init];
annotation.coordinate = annotationCoord;
annotation.identifier = theIdentifier;
annotation.title = theTitle;
annotation.subtitle = theSubtitle
annotation.pinColour = [self getPinColour];
annotation.counter = theCounter;
[theMapView addAnnotation:annotation];
Here is the code where I update the pin (different method to add):
updatePin = true;
pinCounter = mapPin.counter;
CLLocationCoordinate2D annotationCoord;
annotationCoord.latitude = latestPosition.latitude;
annotationCoord.longitude = latestPosition.longitude;
[mapPin setCoordinate:annotationCoord];
mapPin.identifier = theIdentifier;
mapPin.subtitle = theSubtitle;
mapPin.pinColour = [self getPinColour];
I'm not sure what I'm missing. viewForAnnotation is obviously working, it's just not ever called after the initial add! If it were to call this function I'm 100% sure it would work as it does the colour change if I restart the app!
EDIT: Oh and I really don't want to start removing annotations and re-adding them. It's what I'm doing in the short term anyway!
Actually, I dont' know if this worked for you but this is how I did it.
I didn't need to delete the annotation from map. All I need to do is tell the map to give me the annotation view for a parameter annotation. The map will return the correct annotation. From there, I have a property for my custom annotation to identify whether it is an active item, if yes, show the normal pin image, else show full pin image.
-(void)updateAnnotationImage:(CustomAnnotation *)paramAnnotation
{
MKAnnotationView *av = [geoMap viewForAnnotation:paramAnnotation];
if (paramAnnotation.active)
{
av.image = [UIImage imageNamed:#"PinNormal.png"];
}
else
{
av.image = [UIImage imageNamed:#"PinFull.png"];
}
}
Bit late but hopefully it helps others who came across this problem.
Due to the way the map view caches its annotations, you NEED to remove and re-add the annotation if you need to make changes to its appearance. A simple remove & add is the way to go. There is no cache invalidating mechanism but this.
I also found this answer helpful: In which case that mapView:viewForAnnotation: will be called?
Whenever you call addAnnotation method
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id < MKAnnotation >)annotation gets called.
Swift 2.1:
I had the same issue, and found a quick solution, trigger this when needed, also sending it to the main thread would be wise:
var annotationsArray = mapView.annotations
mapView.removeAnnotations(mapView.annotations)
mapView.addAnnotations(arrayIncs)
arrayIncs.removeAll()
Just spent a couple of hours to get this to work on Xamarin; this is a warning for other Xamarin developers. Make sure you use the ViewForAnnotation method and not the GetViewForAnnotation delegate. I was using the wrong method which returned new annotation views instead of the existing ones... of course it wasn't working!

How to get location from map pin in iOS

I am using the MKMapView object and I am able to create pins and place them on the map. What I am trying to do now is get the information back from the pin. For example in my
- (MKAnnotationView*) mapView:(MKMapView *)mapView viewForAnnotation (id<MKAnnotation>)annotation
I create my pins and set them on the map. I am also creating buttons to use when a user clicks on the pin. All that works well and good. Now my question is when that button is clicked how do I get information from that clicked pin? Below is a small sample code of how I currently have it setup. Any advice would be greatly appreciated.
- (MKAnnotationView*) mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
MKPinAnnotationView *annView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:#"location"];
annView.pinColor = MKPinAnnotationColorRed;
annView.animatesDrop = YES;
annView.canShowCallout = YES;
annView.calloutOffset = CGPointMake(-5, 5);
UIButton* callout = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[callout addTarget:self action:#selector(loadDetails:) forControlEvents:UIControlEventTouchUpInside];
annView.rightCalloutAccessoryView = callout;
return annView;
}
- (void)loadDetails:(id)sender
{
//TODO: Get pin coordinates or address and match it back to an array of available address to show details in a new view
}
Any advice is greatly appreciated
Instead of setting the target of your callout, respond to the delegate method
mapView:annotationView:calloutAccessoryControlTapped:
The annotationView will have an annotation property with the coordinate.
You should create a class that derives from MKPinAnnotationView that has a property of id<MkAnnotationView>. During the method above, create this new object instead of the MKPinAnnotationView and set the id<MKAnnotation> property to the annotation passed in.

How to recognize which pin was tapped

I got an app with MKMapView and large number of pins on this map.
Every pin got rightCalloutAccessoryView. I create it in this way:
UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[rightButton addTarget:self action:#selector(showDetails:) forControlEvents:UIControlEventTouchUpInside];
pinView.rightCalloutAccessoryView = rightButton;
How should i know, which pin was tapped? Thnx
In the showDetails: method, you can get the pin tapped from the map view's selectedAnnotations array. Even though the property is an NSArray, just get the first item in the array since the map view only allows one pin to be selected at a time:
//To be safe, may want to check that array has at least one item first.
id<MKAnnotation> ann = [[mapView selectedAnnotations] objectAtIndex:0];
// OR if you have custom annotation class with other properties...
// (in this case may also want to check class of object first)
YourAnnotationClass *ann = [[mapView selectedAnnotations] objectAtIndex:0];
NSLog(#"ann.title = %#", ann.title);
By the way, instead of doing addTarget and implementing a custom method, you can use the map view's calloutAccessoryControlTapped delegate method. The annotation tapped is available in the view parameter:
-(void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view
calloutAccessoryControlTapped:(UIControl *)control
{
NSLog(#"ann.title = %#", view.annotation.title);
}
Make sure you remove the addTarget from viewForAnnotation if you use calloutAccessoryControlTapped.

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