How to set location in map in IOS - ios

I am trying to learn MAP for iPhone.
What I have right now is below.
Created new project
Added framework for MAP
Brought map object on storyboard (UIViewController)
Run the project.
What I see is, its not showing any location. When I change location in xcode, it shows me the dot at location.
What I wanted is, by default it should show me the PIN to the location that I will set by using latitude and longitude. Also the map should be zoomed. What I meant by zoom is, I should see the location with lets say 13 zoom effect. Right now, I see world map on screen.
Any idea how to get this done?

You can center your map around a location by doing something like this:
MKCoordinateRegion mapRegion;
mapRegion.center.latitude = aLatitude;
mapRegion.center.longitude = aLongitude;
mapRegion.span.latitudeDelta = 0.005;
mapRegion.span.longitudeDelta = 0.005;
self.mapView.region = mapRegion;
Use the span values to determine the zoom level you want.
In order to show a pin you need to create an annotation with the coordinates of your location and then add it to the map.
Also, check out this tutorial.. http://www.raywenderlich.com/2847/introduction-to-mapkit-on-ios-tutorial

Dot is showing your current location.
If you want to add a pin with coordinate you should call addAnnotation method with object which conforms to MKAnnotation protocol. Such object has a property coordinate (you should add it to your class):
#property (nonatomic, assign) CLLocationCoordinate2D coordinate;
Also you should add MKMapViewDelegate protocol to your controller and implement -mapView:viewForAnnotation: method. It works as -tableView:viewForRowAtIndexPath:.
- (MKAnnotationView *)mapView:(MKMapView *)_mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
if ([annotation isKindOfClass:[MKUserLocation class]]) {
return nil;
}
static NSString *annotationIdentifier = #"annotation";
MKPinAnnotationView *annotationView = (MKPinAnnotationView *)[_mapView dequeueReusableAnnotationViewWithIdentifier:annotationIdentifier]; // Reusing
if (!annotationView) {
MKPinAnnotationView *pinView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:annotationIdentifier];
pinView.animatesDrop = YES;
annotationView = pinView;
}
else {
annotationView.annotation = annotation; // Reusing already created pin as UITableViewCell does
}
return annotationView;
}
Then when you call
MKMapView *mapView = ...;
id<MKAnnotation> obj = ...;
[mapView addAnnotation:obj];
The pin would be placed on map.
For zoom look there. There is a handy category for those purposes.
If you want to remove current location dot you should find an object with class MKUserLocation in mapView.annotations and then call [mapView removeAnnotation:userLocationDot].

For creating an application with Map you need to implement the MKAnnotation, MKMapViewDelegate delgates.
This is a good tutorial for you.

Related

How to identify XCode MKMapView pins from viewForAnnotation

I am working on an application with an mkmapview, which drops pins onto a mapview.
I need to be able to colour the pins based on information about the pin.
The current code that drops the map pins is:
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id)annotation {
if (annotation == self.mapView.userLocation) return nil;
NSLog(#"annotation = %#", annotation);
static NSString* AnnotationIdentifier = #"AnnotationIdentifier";
MKPinAnnotationView* customPin = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:AnnotationIdentifier];
customPin.pinColor = MKPinAnnotationColorRed;
customPin.animatesDrop = YES;
customPin.canShowCallout = YES;
UIButton* rightButton = [UIButton buttonWithType:UIButtonTypeDetailDisclosure];
customPin.rightCalloutAccessoryView = rightButton;
return customPin;
}
If I change the line:
customPin.pinColor = MKPinAnnotationColorRed;
Then I can change the colour of ALL the dropped pins, but how can I identify which pin is being dropped, so that I can only re-colour the pin if needed?
I added the log line:
NSLog(#"annotation = %#", annotation);
But it returns, for example:
annotation = <MapAnnotation: 0x7feabd749190>
annotation = <MapAnnotation: 0x7feac04edf50>
annotation = <MapAnnotation: 0x7feabd79f860>
How can I use this to identify the pin?
Or should I be colouring the annotation pins in a different location?
You can add any object that conforms to the MKAnnotation protocol to a map as an annotation.
I suggest creating a custom annotation object that has extra properties (like an enum for the pin type, for example)
Then in your viewForAnnotation method, once you make sure it's not the user location annotation, cast the id pointer to your custom annotation object type and check your custom properties to see what type of pin to display (it could be as simple as a switch statement.)

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.

Drop a pin on MKMapView

iPhone newbie is here coming from Java. So my objective at this stage is to allow the user to 'drop a pin' on the map. My initialization of the map looks like this:
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(#"your view did load, I'm going to initizlie the map by your location");
CLLocationCoordinate2D location = theMap.userLocation.coordinate;
NSLog(#"Location found from Map: %f %f",location.latitude,location.longitude);
MKCoordinateRegion region;
MKCoordinateSpan span;
NSLog(#"coordinates: %f %f",location.latitude,location.longitude);
if (TARGET_IPHONE_SIMULATOR) {
NSLog(#"You're using the simulator:");
location.latitude = 40.8761620;
location.longitude = -73.782596;
} else {
location.latitude = theMap.userLocation.location.coordinate.latitude;
location.longitude = theMap.userLocation.location.coordinate.longitude;
}
span.latitudeDelta = 0.001;
span.longitudeDelta = 0.002;
region.span = span;
region.center = location;
[theMap setRegion:region animated:YES];
[theMap regionThatFits:region];
[theMap setMapType:MKMapTypeSatellite];
[theMap setZoomEnabled:YES];
[theMap setScrollEnabled:YES];
[theMap setShowsUserLocation:YES];
}
For the requested pin drop I have
- (MKAnnotationView *)mapView:(MKMapView *)mV viewForAnnotation:(id <MKAnnotation>)annotation {
MKPinAnnotationView *pinView = nil;
if (annotation != theMap.userLocation) {
static NSString *defaultPinID = #"aPin";
pinView = (MKPinAnnotationView *)[theMap dequeueReusableAnnotationViewWithIdentifier:defaultPinID];
if (pinView == nil)
pinView = [[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:defaultPinID] autorelease];
} else {
}
pinView.pinColor = MKPinAnnotationColorRed;
pinView.canShowCallout = YES;
pinView.animatesDrop = YES;
return pinView;
}
I'm not sure I fully understand how this map (theMap) works for pins in viewForAnnotation? I mean, what action the user does will activate the viewForAnnotation method? This code doesn't work and I'm not sure why.
I'm using the simulator so I'm not sure if there's a button I should press or Alt click it?
I'm not sure I fully understand how this map (theMap) works for pins in viewForAnnotation?
MKPinAnnotationView is just another kind of annotation view -- that is, you add an annotation (an object conforming to the MKAnnotation protocol) to the map. When the map wants to display the annotation (maybe because the user scrolled the map so that the annotation is in view), it asks you for a view to use to represent the annotation. At that point, your mapView:viewForAnnotation: method can fetch or create a pin annotation view and return that. The user doesn't do anything directly to trigger mapView:viewForAnnotation:, except for scrolling or zooming.
If you want to the user to be able to drop a pin, that's a different thing. You'll need to provide a view (possibly even a MKPinAnnotationView) that they can drag around. When they indicate that they want to drop the pin (perhaps by lifting their finger), you remove the view and add an appropriate annotation at that point. Then the map view will ask you for a view to represent the annotation by calling its delegate's mapView:viewForAnnotation: method.
This code doesn't work and I'm not sure why.
Have you added any annotations to the map? If so, are you looking at the part of the map where they should be displayed?
I'm guessing that you're looking at the animatesDrop property and expecting it to do the entire user pin-dropping interaction. It doesn't do that. Setting that property to YES merely animates the pin as it appears on the map.
ok, after a while, I understood what went wrong:
theMap.delegate = (id) self;
in the constructor was missing. Once I did that any action by end user will activate other methods (protocols) of the map.

MKPinAnnotationView pinColor

I can't figure out why a MKPinAnnotationView associated (in theory) with a MKPointAnnotation doesn't appear on the map. In fact, the pin appears but it isn't purple as it should be...
Here is the code:
MKPointAnnotation *myPersonalAnnotation= [[MKPointAnnotation alloc]init];
myPersonalAnnotation.title= [appDelegate.theDictionary objectForKey:#"theKey"];
myPersonalAnnotation.coordinate=CLLocationCoordinate2DMake(6.14, 10.7);
MKPinAnnotationView *myPersonalView=[[MKPinAnnotationView alloc] initWithAnnotation:myPersonalAnnotation reuseIdentifier:#"hello"];
myPersonalView.pinColor=MKPinAnnotationColorPurple;
[myMap addAnnotation:myPersonalAnnotation];
If you want to create an annotation view different from the default red pin, you have to create and return it in the map view's viewForAnnotation delegate method.
The map will automatically call the viewForAnnotation delegate method whenever it needs to show some annotation (either the built-in user location or annotations you add).
Remove the local creation of myPersonalView from before the call to addAnnotation and implement the viewForAnnotation method instead.
For example:
//in your current method...
MKPointAnnotation *myPersonalAnnotation= [[MKPointAnnotation alloc]init];
myPersonalAnnotation.title= [appDelegate.theDictionary objectForKey:#"theKey"];
myPersonalAnnotation.coordinate=CLLocationCoordinate2DMake(6.14, 10.7);
[myMap addAnnotation:myPersonalAnnotation];
//...
//add the viewForAnnotation delegate method...
-(MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation
{
//if annotation is the user location, return nil to get default blue-dot...
if ([annotation isKindOfClass:[MKUserLocation class]])
return nil;
//create purple pin view for all other annotations...
static NSString *reuseId = #"hello";
MKPinAnnotationView *myPersonalView = (MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:reuseId];
if (myPersonalView == nil)
{
myPersonalView = [[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:reuseId];
myPersonalView.pinColor = MKPinAnnotationColorPurple;
myPersonalView.canShowCallout = YES;
}
else
{
//if re-using view from another annotation, point view to current annotation...
myPersonalView.annotation = annotation;
}
return myPersonalView;
}
Make sure the map view's delegate property is set otherwise the delegate method won't get called.
In code, use myMap.delegate = self; (eg. in viewDidLoad) or make the connection in Interface Builder if myMap is an IBOutlet.

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!

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