小编use*_*961的帖子

我正在使用下面的代码尝试textField2让textField1用户输入时更新文本内容以匹配textField1.

- (BOOL) textField: (UITextField *)theTextField shouldChangeCharactersInRange: (NSRange)range replacementString: (NSString *)string {    
  if (theTextField == textField1){    
     [textField2 setText:[textField1 text]];    
  }
}

但是,我观察到的输出是......

当textField1为"123"时,textField2为"12"

当textField1为"1234"时,textField2为"123"

......当我想要的是:

当textField1为"123"时,textField2为"123"

当textField1为"1234"时,textField2为"1234"

我究竟做错了什么？

据说Objective-C接受"\ b"作为退格的特殊字符,如何在程序中捕获它？

我的目的是在if语句中捕获它,以便为我的textField启用屏幕字符:

if([someCharacter isEqualToString:@"\ b"]){}

旧SDK解决方案:

- (void)modifyKeyboard:(NSNotification *)notification 
{
    UIView *firstResponder = [[[UIApplication sharedApplication] keyWindow] performSelector:@selector(firstResponder)];

    for (UIWindow *keyboardWindow in [[UIApplication sharedApplication] windows])
        for (UIView *keyboard in [keyboardWindow subviews])
            if([[keyboard description] hasPrefix:@"<UIKeyboard"] == YES)
            {
                MyFancyKeyboardView *customKeyboard = [[MyFancyKeyboardView alloc] initWithFrame: CGRectMake(0, 0, keyboard.frame.size.width, keyboard.frame.size.height);
                                                       [keyboard addSubview: customKeyboard];
                                                       [customKeyboard release];
            }
}

按照上面的方法,我现在发现iOS4是不同的.不起作用.我确信这是由于命名子视图(或排序)的差异.对于iphone SDK 4,有谁知道如何解决同样的问题？