iPhone 和输入,键盘相关的属性

当文本输入时, 文本框有几中选择用于辅助输入:

selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];--------------------- (void)keyboardWillShow:(NSNotification *)note { // create custom button UIButton *doneButton = [UIButton buttonWithType:UIButtonTypeCustom]; doneButton.frame = CGRectMake(0, 163, 106, 53); doneButton.adjustsImageWhenHighlighted = NO; [doneButton setImage:[UIImage imageNamed:@"DoneUp.png"] forState:UIControlStateNormal]; [doneButton setImage:[UIImage imageNamed:@"DoneDown.png"] forState:UIControlStateHighlighted]; [doneButton addTarget:self action:@selector(doneButton:) forControlEvents:UIControlEventTouchUpInside]; // locate keyboard view UIWindow* tempWindow = [[[UIApplication sharedApplication] windows] objectAtIndex:1]; UIView* keyboard; for(int i=0; i<[tempWindow.subviews count]; i++) { keyboard = [tempWindow.subviews objectAtIndex:i]; // keyboard view found; add the custom button to it if([[keyboard description] hasPrefix:@"<UIKeyboard"] == YES) [keyboard addSubview:doneButton]; }}?