In my app I have two functionality when my tableview loads ,in the mapview all the pins are shown corresponding to tableData.NOw I have search bar which gives another set of values which I have to show on my mapView.Everything is working fine but second time previous pins are also shown means prevoius annotations are not deleted .
So please tell me how to remove prevoius annotation so that I can show only relavent pins on mapView
Thanks in advance
Simply use the MKMapView instance method "removeAnnotations:":
-(void)removeAnnotations:(NSArray *)annotations
http://developer.apple.com/library/ios/#documentation/MapKit/Reference/MKMapView_Class/MKMapView/MKMapView.html
If you want to remove all of them you can do somethign like :
[mapView removeAnnotations:mapView.annotations];
P.S: Beware that you might want to iterate through the annotations not to remove the userLocation (blue dot)
Hope this helps,
Vincent
I got my answer my self:-
mapAddAnnotations is my arrayname and map is my mkmapview object.
[map removeAnnotations:self.mapAddAnnotations];
Related
I set the mapView's showUserLocation property to YES, and it does nothing. I was able to use a CLLocationManager to center the map on the user's current location, but there's no pin/dot on the screen. How can I put a pin on the map for the exact location of the user?
This has messed me up several times but its an easy fix
The problem is that your code is:
[self.mapView showUserLocation:YES];
Should be:
[self.mapView setShowsUserLocation:YES]
Also make sure you have set the delegate as well
IN Nib name you can set showuserlocation to mark for Mapview.
I have a custom placemark with title and subtitle. The subtitle is actually displaying the address of the dropped pin using the reverse geocoder.
I have a button which has an action to drop the pin. This action gets the location coordinates of the user, and then calls [geocoder start] which gets the full address with Reverse Geocoder and generates the custom annotation and then calls [mapView addAnnotation:customPlacemark].
My problem is that using this sequence order, when there's no a WiFi connection (only 3G or maybe Edge) the pin takes a lot to drop because it's watigin to get the reverse geocoding info.
So basically I need to drop the pin without a subtitle and from the viewDidAnnotation call the geocoder and inside the reverseGeocoder update the subtitle but I'm not sure how to do that.
I want to display the annotation without the address details and update it when it gets the information from the reverse geocoder.
Any suggestions?
Thanks in advance
MKMapView observes changes its annotations via KVO. Therefore if you update your annotation's properties in a KVO compliant manner, it should Just Work.
For example, when the reverse geocoder returns an address for your annotation, you first announce the title and subtitle properties are about to change:
[self willChangeValueForKey:#"title"];
[self willChangeValueForKey:#"subtitle"];
Note that the above code is assumed to be in the annotation class.
Then update the annotation with information from the geocoder. When you are done:
[self didChangeValueForKey:#"subtitle"];
[self didChangeValueForKey:#"title"];
Note the order changed for didChangeValueForKey: as these need to be nested properly, somewhat like HTML tags.
This also works for the coordinate property, that will cause the pin to move.
I'd place the annotation, keep a reference to it in a property, then when your reverse geocoder calls back use the reference to the annotation and update its properties.
I'm displaying a MKMapView with MKAnnotations some of which are selected and showing their Annotation.
I am trying to grab an image of the displayed map and annotations using the -renderInContext.
90% of the time the Map, MKPinAnnotationView's and selected annotations are correctly captured.
The other 10% of the time the image is missing something, usually the MKPinAnnotationViews or their annotations if selected.
I've added code to deal with the Map itself loading it's map data.
But I haven't been able to track down something that would indicate to me that all of the visible MKPinAnnotationView's have been drawn
and if selected their annotations displayed??
the closest hint I've come across is the addObserver, although I haven't figured out what could be observed that would tell me when all of the drawing is done.
Thoughts?
ok I'm an idiot...
I finally tracked down the problem. In my viewForAnnotation routine in the MKMapView Delegate protocol I wasn't correctly setting values for reused MKPinAnnotationView's.
So some of the time I would reuse a view that had .canShowCallout set to YES and other times I'd reuse a view that had .canShowCallout set to NO.
.<
Try using the MKMapViewDelegate didAddAnnotationViews method.
If in that method, the drawing is still not ready for your requirements, you could then in there call your capturing method with performSelector:withObject:afterDelay:.
I have an interface with a mapView and UITableView. Data is loaded from a server, and the annotations are created and added to the map with
[mapView addAnnotation:truck]
the tableview is then populated using the array thats retured from
[mapView annotations]
once this process is completed, i check the number of annotations on the map with [[mapView annotations] count] called whenever i click on a cell in the table and its equal to the number it ought to be, so all the annotations are getting added onto the mapView, but for some reason I cant see any annotations in the simulator.
The images are named just as they are assigned in the custom AnnotationView, the loadAnnotation function is done properly, etc... i dont know what it could be but ive looked at the associate between the image file and wheres its loaded a hundred times to find a discrepancy, but it all looks fine.
One interesting point is that when i print and coordinate value after clicking on the cell (remember this data comes straight from [mapView annotations], it looks good... but for whatever reason the annotation view isnt being displayed.
so i suppose if i could have the answer to one question it would be, what are possible causes for a mapView to contain several annotations, but to not show any on the map?
Thanks
EDITED WITH IMPORTANT ADDITIONAL INFO
There appears to be a disconnect between what is being displayed on my map in the simulator and what im seeing in the mapView object. For example, when i select a row in the tableView, I am calling:
[mapView setRegion:MKCoordinateRegionMake([annotation coordinate], MKCoordinateSpanMake(.01, .01)) animated:YES];
and this has no effect on the map in the simulator. I have checked that the coordinate being passed is actually a valid coordinate, but it doesnt seem to matter because the map is being unresponsive. I thought it could be something wrong with my .xib, but its all connected properly. delegate is the outlet and mapView as a referencing outlet.
Does anyone now understand what may be happening?
This really looks like missing images.
Try replacing your custom annotations with MKPinAnnotations to test, and see if your annotations are visible then.
Have you implemented the following delegate function ?
(MKAnnotationView*) mapView:(MKMapView *)mapView viewForAnnotation:(id )annotation;
This line:
mapView = [[MKMapView alloc] initWithFrame:self.view.bounds];
was creating messing everything up. once i commented it out, the app began working fine.
I am building an app that tracks user location on map. I can insert a pin easily, but when the location is changed, the app quits.
I have set the default coordinates to 0,0 in viewdidload: method and I have added a pin at that location. I have done this because I want to remove the pin when location is updated and then insert the pin again on new location.
Here is the code which I have written in -(void)locationManager: didUpdateToLocation:fromLocation: method.
[mapview removeAnnotation:myannotation];
CLLocationCoordinate2D currentlocation;
currentlocation.latitude=newLocation.coordinate.latitude;
currentlocation.longitude=newLocation.coordinate.longitude;
myannotation=[[[CSMapAnnotation alloc]initWithCoordinate:currentlocation annotationType:CSMapAnnotationTypeStart title:#"My Location"] autorelease];
[mapview addAnnotation:myannotation];
Here, myannotation is the pin which I want to add,newLocation is the updated location and CSMapAnnotation will return annotation view.
The problem is my app crashes everytime. I was able to get warning message on console before crashing. Here is the message:
"An instance 0x182020 of class CSMapAnnotation is being deallocated while key value observers are still registered with it. Observation info is being leaked, and may even become mistakenly attached to some other object."
So, plz help if anyone has faced the same problem...
A few things to look out for:
MKMapView already has a showsUserLocation attribute that tracks the user's location for you with the pulsing blue-dot thing. If you want to separately set a pin on that location, you can get the userLocation attribute from the mapview.
The crashing bug could be because of the autorelease call. Easiest way to fix it is to make myannotation a property with a retain attribute, then take out the autorelease and instead of myannotation use self.myannotation.
Not really clear what you mean by setting "default coordinates to 0, 0." If these are lat/longs then you're putting a pin in Greenwich, England :-) You don't really need to continually add and remove annotations. You can add them once then adjust their position as needed.
I am thinking it is not liking your autorelease tag for myannotation, when you add the annotation to the map it might not be being retained, and then it just deallocates and crash, thats what i can think of from looking at the code you posted. Hope it helps
I just experienced this same problem and it had something to do with the coordinates of the annotation. I was already ignoring 0,0 but for some reason users were inputting -180,-180 (maybe from a device where we couldnt determine the location?)
anyways - as soon as I started ignoring -180,-180 the problem went away.
hope this helps.