I have an app which is providing a zoomable MKMapView to the user. I want to be able to store the user's preferred coordinates and zoom level for when the map view is first displayed.
Currently, in viewDidLoad, I am providing a default set of coordinates and zoom level for the initial map presentation:
zoomLocation.latitude = 55.50;
zoomLocation.longitude = -5.50;
// specify size of region to display
MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(zoomLocation, 340.0*METERS_PER_MILE, 340.0*METERS_PER_MILE);
// auto adjust region to fit screen
MKCoordinateRegion adjustedRegion = [mapView regionThatFits:viewRegion];
// display the new region
[mapView setRegion:adjustedRegion animated:YES];
What I am trying to do is, when the user scrolls and zooms the map to their preferred default view, they can hit the "Set Default" button and store the required properties to implemented in future whenever the view loads.
To store the coordinates of the user's selected view, I have this:
// gets coordinates of currently viewed map image
CGPoint pointCentrePoint = CGPointMake(mapView.frame.size.width/2, mapView.frame.size.height/2);
centrePoint = [mapView convertPoint:pointCentrePoint toCoordinateFromView:mapView];
NSLog(#"LAT: %f LON: %f", centrePoint.latitude, centrePoint.longitude);
What I'm struggling with is how to store the user's selected MKCoordinateRegion, or zoom level. Is there a way I can access this property for the current view, so it can be reused in future when the view loads?
Unlike the JavaScript Google Maps api, the MKMapView doesn't have a readily available "zoom level" property (it isn't really necessary for your purpose).
Work with the center and span values in the region property.
This question gives an example of how to save/load the region to NSUserDefaults.
Related
I need to create ViewController with MKMapView. When it opens, there are should appear current location and slowly zooming out for 10 seconds (or less, it doesn't matter actually). And when animation completed application should perform segue to the next ViewController. Any ideas?
There is no "direct" method for setting a zoom level. You can, however, simulate this by setting the distance, which causes the image to resize.
CLLocationCoordinate2D noLocation;
MKCoordinateRegion viewRegion = MKCoordinateRegionMakeWithDistance(noLocation, 500, 500);
MKCoordinateRegion adjustedRegion = [self.mapView regionThatFits:viewRegion];
[self.mapView setRegion:adjustedRegion animated:YES];
self.mapView.showsUserLocation = YES;
You can either loop this, or simply set it twice, first to a BIG area and then the zoomed in area, and let the MapView's default animation do its thing.
I have a mapview in xcode, which is all working well.
What my page does just now is like this:
downloads a bunch of data and locations from a backend database
populates a mapview with locations and drops pins
populates a table underneath the mapview
That all works great, and I end up with a mapview with a load of pins, and a tableview that has the details of those pins.
What I want to do now, is allow the user to tap on a row from the tableview, and have the map zoom and centre to the corresponding map pin, and then automatically activate the annotation pin callout.
In my 'didselectrow' method, I have the following:
MKCoordinateSpan span = MKCoordinateSpanMake(0.1f, 0.1f);
CLLocationCoordinate2D coordinate = { [item.latitude floatValue], [item.longitude floatValue] };
MKCoordinateRegion region = { coordinate, span };
[self.mapView setRegion:region animated:YES];
This works great too. Tapping on the table row will zoom to and centre the map pin at this location.
I just can't get the last step of firing the annotation pin callout to work.
I have tried:
[mapview annotationsInMapRect:mapview.visibleMapRect];
But this isn't working, and it is possible that there still might be 2 or 3 map pins in the visible area.
What I need to do is to get the pin nearest to the centred location (see above - item.latitude / item.longitude) to automatically open it's callout.
Everything in the code is set up and working, and the map pins have callouts that fire when tapped on, I just need this last stage of having the pin nearest the centre location to open automatically.
Can anyone help with this?
I have tried various other suggestions on SO, but none seem to fit this requirement.
I think I have got solution for your problem you need to use this [_mapView setSelectedAnnotations:#[[[self.mapView annotations] lastObject]]];
For testing I have created an small project that have these 2 methods.
- (IBAction)buttonTouched:(id)sender {
[_mapView showAnnotations:[self.mapView annotations] animated:YES];
[self performSelector:#selector(showAnnotationCallOut) withObject:nil afterDelay:1.0f];
}
- (void) showAnnotationCallOut {
[_mapView setSelectedAnnotations:#[[[self.mapView annotations] lastObject]]];
}
Note: I have called just one annotation for test that why I am calling last object. You'll need to call it for specific annotation of your annotation array.
Edit: According to Richerd's comment here is solution for problem of finding the annotion and showing the callout fro that.
for (MapViewAnnotation *annotion in [self.mapView annotion]) {
if ([annotion.identifire isEqualToString:annotationToCallCallOutIdentifier]) {
//[_mapView setSelectedAnnotations:#[annotation]];
[_mapView selectAnnotation:annotation animated:YES];
break;//don't break if there are can be more than one callouts
}
}
I have a MKPinAnnotationView that is always in the center of the map. When panning and zooming
the pin gives me the center coordinates (lat/long) of the map.
Currently when you zoom in, it just zooms into wherever your directing the map to zoom into.
I'd really like to lock the zoom onto the pin.
Any ideas on how I'd achieve this?
Assuming by MKPinAnnotation you mean MKPinAnnotationView, you can access the annotation's coordinate and use that to create a region and subsequently set the region of the mapView to that region centered on the coordinate:
MKCoordinateRegion region = MKCoordinateRegionMake(pin.annotation.coordinate, MKCoordinateSpanMake(.05, .05));
[self.mapView setRegion:region animated:YES];
I have a question regarding setting the region on my MKMapView.
I need to set the mapview to display a specific region when my view first loads.
The north east and south west latitude and longitude of this region is:
North East Coordinate Lat:59.623724 Long:2.911587
South West Coordinate Lat:49.004833 Long:-11.361825
Further to this, I would like to 'lock' the mapview to this region. Ideally the lock will be transparent, i.e: the coordinates above represent the maximum extent of the MKMapView. However if it is simply a case of checking the northeast and southwest coordinates within
- (void)mapView:(MKMapView *)aMapView regionDidChangeAnimated:(BOOL)animated
and resetting the view if they exceed my maximum range, that would be acceptable to me also.
Many thanks for any pointers on this matter.
EDIT:
Regarding the first part of my question, I have figured out I can set the initial region on the MKMapView using the following code:
CLLocationCoordinate2D neCoord;
neCoord.latitude = 59.787643;
neCoord.longitude = 3.025857;
CLLocationCoordinate2D swCoord;
swCoord.latitude = 49.394171;
swCoord.longitude = -11.036642;
MKCoordinateRegion region;
region.center.latitude = neCoord.latitude - (neCoord.latitude - swCoord.latitude) * 0.5;
region.center.longitude = neCoord.longitude + (swCoord.longitude - neCoord.longitude) * 0.5;
region.span.latitudeDelta = fabs(neCoord.latitude - swCoord.latitude); // Add a little extra space on the sides
region.span.longitudeDelta = fabs(swCoord.longitude - neCoord.longitude); // Add a little extra space on the sides
region = [self.mapView regionThatFits:region];
[self.mapView setRegion:region animated:YES];
First, you'll need to make sure you set the region on the map view after the view has been displayed. If you set it before the map has loaded, it probably won't center on that region. Once you've done that, just set self.mapView.zoomEnabled = NO; and self.mapView.scrollEnabled = NO; and it will prevent the user from moving the map around.
If you want to lock the maximum bounds the user can view but still allow scrolling and zooming, you will have to use -mapView:regionDidChangeAnimated: and 'bump' the user back inside your bounds if they leave it. Note that the user experience for this will probably suck - they'll pan around, let go, and then the map will suddenly move back to the region you defined. You could try using -mapView:regionWillChangeAnimated: and modify the map region if they left your boundaries, that could be a little less jarring.
How do I reset an MKMapView back to the world view zoom level?
The map rect for the world is stored as a constant named MKMapRectWorld.
MKCoordinateRegion worldRegion = MKCoordinateRegionForMapRect(MKMapRectWorld);
map.region = worldRegion;
One other way is to set the zoom level of the map. Although the MapKit framework does not support zoom levels as Google Maps API does, you can use this category extension written by Troy Brant.
Set the center coordinate to 0, 0 with zoom level 0 to get the same result.
[map setCenterCoordinate:CLLocationCoordinate2DMake(0, 0) zoomLevel:0 animated:0];
Try this:
MKCoordinateRegion region = MKCoordinateRegionMake(mapView.centerCoordinate, MKCoordinateSpanMake(180, 360));
[mapView setRegion:region animated:YES];
This will set a new region for the map view using the current center coordinate, and the maximum possible span (180 degrees of latitude, 360 degrees of longitude).
For those hoping to do this in Swift:
let region = MKCoordinateRegion(.world)
mapView.setRegion(region, animated: true)
MKMapView can not zoom out to show the whole world. No matter what you are using, MKMapRectWorld, zoom level 0, or MKCoordinateSpanMake(180, 360).