Instance Method

setNeedsDisplay

Marks the layer’s contents as needing to be updated.

Declaration

- (void)setNeedsDisplay;

Discussion

Calling this method causes the layer to recache its content. This results in the layer potentially calling either the displayLayer: or drawLayer:inContext: method of its delegate. The existing content in the layer’s contents property is removed to make way for the new content.

See Also

Updating Layer Display

- setNeedsDisplayInRect:

Marks the region within the specified rectangle as needing to be updated.

needsDisplayOnBoundsChange

A Boolean indicating whether the layer contents must be updated when its bounds rectangle changes.

- displayIfNeeded

Initiates the update process for a layer if it is currently marked as needing an update.

- needsDisplay

Returns a Boolean indicating whether the layer has been marked as needing an update.

+ needsDisplayForKey:

Returns a Boolean indicating whether changes to the specified key require the layer to be redisplayed.