Possible Duplicate:
Understanding @Protocols in Objective-C
Could somebody explain what a protocol is in Objective C.
The reason is that on apples
MPMediaPlayback Protocol Reference f
has methods to control the video play back, ie I'm trying to get stop to work. The apples documentation at
ttp://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/ObjectiveC/Chapters/ocProtocols.html
says it declarers a interface for others to create. So I was assuming this would mean MPMoviePlayerController would have all the methds in Mpmmediaplayback? Well I try the following [mp stop] and it did nothing. I tried other functions declered in MPM and non of nthem work.
Could somebody explain how a protocol works?