如何使用return/enter鍵創建UIKeyCommand？

Question

我想編一個僅使用[return]鍵的UIKeyCommand。到目前爲止，我已經試過：

UIKeyCommand *selectCommand = [UIKeyCommand keyCommandWithInput:@"\n" modifierFlags:0 action:@selector(chooseSelection:)]; 

還有的回車鍵沒有全局常量，像有對上，下，左，右，和逃生（從UIResponder.h）：

// These are pre-defined constants for use with the input property of UIKeyCommand objects. 
UIKIT_EXTERN NSString *const UIKeyInputUpArrow   NS_AVAILABLE_IOS(7_0); 
UIKIT_EXTERN NSString *const UIKeyInputDownArrow  NS_AVAILABLE_IOS(7_0); 
UIKIT_EXTERN NSString *const UIKeyInputLeftArrow  NS_AVAILABLE_IOS(7_0); 
UIKIT_EXTERN NSString *const UIKeyInputRightArrow  NS_AVAILABLE_IOS(7_0); 
UIKIT_EXTERN NSString *const UIKeyInputEscape   NS_AVAILABLE_IOS(7_0); 

是還有什麼我可以嘗試捕獲返回/輸入密鑰？

Answer 1

使用@"\r"作爲換行符而不是@"\n"應該起作用。