Sets the message to send to the animation delegate when the animation starts.
- iOS 2.0+
- tvOS 9.0+
The message to send to the animation delegate before animations start. The default value is
NULL. This selector should be of the form:
- (void)animation. Your method must take the following arguments:
Did Start:(NSString *)animation ID context:(void *)context
An optional application-supplied context. This is the context data passed to the
beginmethod. This argument can be
If you specify an animation delegate for a begin/commit set of animations, you use this method to specify the selector to call before the animations begin. This method does nothing if called from outside of an animation block. It must be called between calls to the
commit methods. This selector is set to
NULL by default.
Use of this method is discouraged in iOS 4.0 and later. If you are using the block-based animation methods, you can include your delegate’s start code directly inside your block.