如何使用返回/输入键创建 UIKeyCommand？

Question

I'd like to make a UIKeyCommand that uses only the [return] key. So far I've tried:

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

There's no global constant for the enter key, like there is for up, down, left, right, and escape (from 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);

Is there anything else I could try to capture the return/enter key?

Answer 1

使用@"\\r"回车而不是@"\\n"换行应该可以工作。