what is Responder chain in iPhone SDK ?? How it works? -

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what responder chain in iphone sdk ?? how works ?

see documentation:

if first responder [to event or action message] cannot handle event or action message, forwards “next responder” in linked series called responder chain. responder chain allows responder objects transfer responsibility handling event or action message other objects in application.
if object in responder chain cannot handle event or action, resends message next responder in chain. message travels chain, toward higher-level objects, until handled. if isn't handled, application discards it.


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