Deprecated MKOverlayView Methods

A method identified as deprecated has been superseded and may become unsupported in the future.

Deprecated in iOS 7.0

overlay

The overlay object containing the data for drawing. (read-only) (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

@property (nonatomic, readonly) id <MKOverlay> overlay
Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Related Sample Code
Declared In
MKOverlayView.h

canDrawMapRect:zoomScale:

Returns a Boolean value indicating whether the overlay view is ready to draw its content. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (BOOL)canDrawMapRect:(MKMapRect)mapRect zoomScale:(MKZoomScale)zoomScale
Parameters
mapRect

The map rectangle that needs to be updated.

zoomScale

The current scale factor applied to the map.

Return Value

YES if this view is ready to draw its contents or NO if it is not.

Discussion

Overlay views can override this method in situations where they may depend on the availability of other information to draw their contents. For example, an overlay view showing traffic information might want to delay drawing until it has all of the traffic data it needs. In such a case, it can return NO from this method to indicate that it is not ready.

If you return NO from this method, your application is responsible for calling the setNeedsDisplayInMapRect:zoomScale: method when the overlay view subsequently becomes ready to draw its contents.

The default implementation of this method returns YES.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

drawMapRect:zoomScale:inContext:

Draws the contents of the overlay view. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (void)drawMapRect:(MKMapRect)mapRect zoomScale:(MKZoomScale)zoomScale inContext:(CGContextRef)context
Parameters
mapRect

The map rectangle that needs to be updated. You can use this rectangle to limit drawing to only the portion of the view that changed.

zoomScale

The current scale factor applied to the map content. You can use this value for configuring the stroke width of lines or other attributes that might be affected by the scale of the view’s content.

context

The graphics context to use for drawing the view’s content.

Discussion

The default implementation of this method does nothing. Subclasses are expected to override this method (instead of the drawRect: method) and use it to draw the contents of the view.

In your drawing code, you should specify the position of any rendered content relative to the map itself and not relative to the view’s bounds or frame. In other words, compute the position and size of any overlay content using map points and map rectangles, convert those values to CGPoint and CGRect types (using the methods of this class), and then use the converted points to build paths or specify the rendering location for items.

You should also not make assumptions that the view’s frame matches the bounding rectangle of the overlay. The view’s frame is actually bigger than the bounding rectangle to allow you to draw lines for things like roads that might be located directly on the border of that rectangle. For some types of content, such as gradients, this also means that you might need to apply a clipping rectangle to context to ensure drawing is contained to the correct area.

It is recommended that you use Core Graphics to draw any content for your overlays. If you choose to use UIKit classes and methods for drawing instead, you must push the specified graphics context onto the context stack (using the UIGraphicsPushContext function) before making any drawing calls. When you are done drawing, you must similarly pop the graphics context off the stack using the UIGraphicsPopContext. During drawing, you may draw content normally but should avoid manipulating views and other classes that are safe to use only from the application’s main thread.

To improve drawing performance, the map view may tile overlays that become large enough and render the tiles from separate threads. Your implementation of this method must therefore be capable of safely running from multiple threads simultaneously. In addition, you should avoid drawing the entire contents of the overlay each time this method is called. Instead, your implementation should always take the mapRect parameter into consideration and avoid drawing content outside that rectangle. Failure to do so could lead to performance problems.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

initWithOverlay:

Initializes and returns the overlay view and associates it with the specified overlay object. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (id)initWithOverlay:(id <MKOverlay>)overlay
Parameters
overlay

The overlay object to use when drawing the overlay on the map. This object provides the data needed to draw the overlay’s shape. This object is retained by the overlay view.

Return Value

An initialized overlay object.

Discussion

Upon initialization, the frame of the overlay view is set to CGRectZero. The map view sets the size and position of the view at display time, and you should not change those values yourself.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

mapPointForPoint:

Returns the map point that corresponds to the specified point in the overlay view. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (MKMapPoint)mapPointForPoint:(CGPoint)point
Parameters
point

The point in the view’s coordinate system that you want to convert.

Return Value

The point on the two-dimensional map projection corresponding to the specified point.

Special Considerations

Because the bounds and frame rectangles of an overlay view do not change after the view has been created, you may call this method from multiple threads simultaneously. Therefore, you may call this method safely from your view’s drawMapRect:zoomScale:inContext: method.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

mapRectForRect:

Returns the map rectangle that corresponds to the rectangle in the overlay view’s coordinate system. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (MKMapRect)mapRectForRect:(CGRect)rect
Parameters
rect

The rectangle specified in the receiver’s coordinate system.

Return Value

The rectangle on the two-dimensional map project that corresponds to the specified view rectangle.

Special Considerations

Because the bounds and frame rectangles of an overlay view do not change after the view has been created, you may call this method from multiple threads simultaneously. Therefore, you may call this method safely from your view’s drawMapRect:zoomScale:inContext: method.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

pointForMapPoint:

Returns the point in the overlay view that corresponds to specified point on the map. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (CGPoint)pointForMapPoint:(MKMapPoint)mapPoint
Parameters
mapPoint

A point on the two-dimensional map projection. If you have a coordinate value (latitude and longitude), you can use the MKMapPointForCoordinate function to convert that coordinate to a map point.

Return Value

The point in the receiver’s coordinate system that corresponds to the map point.

Special Considerations

Because the bounds and frame rectangles of an overlay view do not change after the view has been created, you may call this method from multiple threads simultaneously. Therefore, you may call this method safely from your view’s drawMapRect:zoomScale:inContext: method.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

rectForMapRect:

Returns the rectangle in the overlay view that corresponds to the specified rectangle on the map. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (CGRect)rectForMapRect:(MKMapRect)mapRect
Parameters
mapRect

A rectangle on the two-dimensional map projection.

Return Value

The rectangle specified in the receiver’s coordinate system.

Special Considerations

Because the bounds and frame rectangles of an overlay view do not change after the view has been created, you may call this method from multiple threads simultaneously. Therefore, you may call this method safely from your view’s drawMapRect:zoomScale:inContext: method.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

setNeedsDisplayInMapRect:

Invalidates the view in the given map rectangle at all zoom scales. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (void)setNeedsDisplayInMapRect:(MKMapRect)mapRect
Parameters
mapRect

The portion of the overlay that needs to be updated. This value is specified using a map rectangle and not view coordinates. You can convert from a view rectangle to a map rectangle using the mapRectForRect: method.

Discussion

Marking a rectangle as invalid causes that portion of the view to be redrawn during the next update cycle. This method invalidates the overlay regardless of the current zoom scale associated with the map.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h

setNeedsDisplayInMapRect:zoomScale:

Invalidates the view in the given map rectangle but only at the specified zoom scale. (Deprecated in iOS 7.0. Use an MKOverlayRenderer object instead.)

- (void)setNeedsDisplayInMapRect:(MKMapRect)mapRect zoomScale:(MKZoomScale)zoomScale
Parameters
mapRect

The portion of the overlay that needs to be updated. This value is specified using a map rectangle and not view coordinates. You can convert from a view rectangle to a map rectangle using the mapRectForRect: method.

zoomScale

The zoom scale for which you want to invalidate the overlay.

Discussion

Marking a rectangle as invalid causes that portion of the view to be redrawn during the next update cycle. This method invalidates the overlay only when it is drawn at the specified zoom scale.

Availability
  • Available in iOS 4.0 and later.
  • Deprecated in iOS 7.0.
Declared In
MKOverlayView.h