Cannot find protocol declaration for & quot; RefreshAudioL

[Html] Today, a very abnormal problem gets stuck: cannot find protocol declaration for "RefreshAudioListViewDelegate" <p> </p> <span style = "color: rgb (186, 45,162); font-family: Menlo; font-size: 11px; "> 1. in PlayerController. h </span> Custom a proxy <span style = "font-family: Menlo; font-size: 11px; "> RefreshAudioListViewDelegate </span> </p> <p style =" margin-top: 0px; margin-bottom: 0px; font-size: 11px; font-family: Menlo; color: rgb (2 09, 46, 27); "> </p> <pre name =" code "class =" html "> # import" <span style = "font-family: Menlo; font-size: 11px; "> PlayerListViewController. h </span> "@ protocol RefreshAudioListViewDelegate <NSObject>-(void) updateCurrentPlayedAudio :( NSUInteger) currentPlayedIndex; @ end www.2cto.com @ interface PlayerController: NSObject </pre> <p> </p> <p style = "margin-top: 0px; margin-bottom: 0px; font-size: 11px; font- Family: Menlo; color: rgb (209,46, 27) "> <br> </p> <p style =" margin-top: 0px; margin-bottom: 0px; font-size: 11px; font-family: Menlo; color: rgb (209,46, 27) "> <br> </p> <br> 2. in <span style = "font-family: Menlo; font-size: 11px"> PlayerListViewController. h </span> <pre> </pre> <pre name = "code" class = "html"> # import "PlayerController. h "@ class PlayerController; @ interface PlayerListViewController: UIViewControlle R <RefreshAudioListViewDelegate> {PlayerController * playerController;} </pre> <br> <p style = "margin-top: 0px; margin-bottom: 0px; font-size: 11px; font-family: Menlo; color: rgb (209,46, 27) "> the compiler prompts" cannot find protocol declaration for "RefreshAudioListViewDelegate" </p> <p style = "margin-top: 0px; margin-bottom: 0px; font-size: 11px; font-family: Menlo; color: rgb (209,46, 27) "> Cause Analysis: </p> <p style =" margin-t Op: 0px; margin-bottom: 0px; font-size: 11px; color: rgb (209,46, 27) "> <span style =" font-family: menlo "> compilation sequence in the compiler: </span> </p> <pre name =" code "class =" html "style =" font-family: Menlo; "> <span style =" font-family: Menlo; font-size: 11px; "> 1. playerListViewController. # import "PlayerController. h ", the compiler will run to PlayerController. h. </Span> </pre> <pre name = "code" class = "html" style = "font-family: Menlo;"> <span style = "font-family: menlo; font-size: 11px; "> 2. in PlayerController. # import "PlayerListViewController. h ", the compiler will load content in PlayerListViewController again. </Span> </pre> <pre name = "code" class = "html"> <span style = "font-size: 11px; "> <span style =" font-family: Menlo; "> 3. when you see </span> <pre name = "code" class = "html" style = "font-family: Menlo;"> @ interface PlayerListViewController: when UIViewController <RefreshAudioListViewDelegate> is specified, the compiler reports an error because the statements defining the proxy in PlayerController are not loaded: </pre> <pre name = "code" class = "html"> <pre name = "code" class = "html" style = "font-family: Menlo; "> cannot find protocol declaration for" RefreshAudioListViewDelegate "</pre> <pre name =" code "class =" html "style =" font-family: Menlo; "> </pre> <pre name =" code "class =" html "> <span style =" font-family: Menlo; "> solution: </span> </pre> <pre name = "code" class = "html"> <span style = "font-family: Menlo;"> Delete PlayerController. </span> <pre name = "code" class = "html"> # import "<span style =" font-family: Menlo; font-size: 11px; "> PlayerListViewController. h </span> "</pre> <p> </p> <pre> </pre> <p> </p> </pre>