iOS - 双击 uibutton答案

【问题标题】：iOS - Double tap on uibuttoniOS - 双击 uibutton
【发布时间】：2012-11-24 20:37:59
【问题描述】：

我有一个按钮，我正在测试它的点击，点击它改变背景颜色，点击两下另一种颜色，再点击三下另一种颜色。代码是：

- (IBAction) button 
{
    UITapGestureRecognizer *tapOnce = [[UITapGestureRecognizer alloc] initWithTarget:self  action:@selector(tapOnce:)];
    UITapGestureRecognizer *tapTwice = [[UITapGestureRecognizer alloc] initWithTarget:self  action:@selector(tapTwice:)];
    UITapGestureRecognizer *tapTrice = [[UITapGestureRecognizer alloc] initWithTarget:self  action:@selector(tapTrice:)];

    tapOnce.numberOfTapsRequired  = 1;
    tapTwice.numberOfTapsRequired = 2;
    tapTrice.numberOfTapsRequired = 3;

    //stops tapOnce from overriding tapTwice
    [tapOnce requireGestureRecognizerToFail:tapTwice];
    [tapTwice requireGestureRecognizerToFail:tapTrice];

    //then need to add the gesture recogniser to a view - this will be the view that recognises the gesture
    [self.view addGestureRecognizer:tapOnce];
    [self.view addGestureRecognizer:tapTwice];
    [self.view addGestureRecognizer:tapTrice];
}

- (void)tapOnce:(UIGestureRecognizer *)gesture
{ 
    self.view.backgroundColor = [UIColor redColor]; 
}

- (void)tapTwice:(UIGestureRecognizer *)gesture
{
    self.view.backgroundColor = [UIColor blackColor];
}

- (void)tapTrice:(UIGestureRecognizer *)gesture
{
    self.view.backgroundColor = [UIColor yellowColor]; 
}

问题是第一个水龙头不起作用，另一个是。如果我在没有按钮的情况下使用此代码，它会完美运行。谢谢。

【问题讨论】：

您是否在点击按钮时添加此手势？为什么不将它添加到 viewDidLoad 中？
因为我必须只在一小部分视图上使用这个手势。
但是你的代码在整体上设置手势self.view。那么你应该按照我的答案进行更改。

标签： objective-c ios xcode button gesture

【解决方案1】：

如果您希望在点击按钮时更改颜色，您应该在viewDidLoad 方法左右的按钮上添加这些手势，而不是在同一个按钮操作上。上面的代码将重复添加点击按钮的手势到self.view而不是button。

- (void)viewDidLoad {
      [super viewDidLoad];
      UITapGestureRecognizer *tapOnce = [[UITapGestureRecognizer alloc] initWithTarget:self  action:@selector(tapOnce:)];
      UITapGestureRecognizer *tapTwice = [[UITapGestureRecognizer alloc] initWithTarget:self  action:@selector(tapTwice:)];
      UITapGestureRecognizer *tapTrice = [[UITapGestureRecognizer alloc] initWithTarget:self  action:@selector(tapTrice:)];

      tapOnce.numberOfTapsRequired = 1;
      tapTwice.numberOfTapsRequired = 2;
      tapTrice.numberOfTapsRequired = 3;
      //stops tapOnce from overriding tapTwice
      [tapOnce requireGestureRecognizerToFail:tapTwice];
      [tapTwice requireGestureRecognizerToFail:tapTrice];

      //then need to add the gesture recogniser to a view - this will be the view that recognises the gesture
      [self.button addGestureRecognizer:tapOnce]; //remove the other button action which calls method `button`
      [self.button addGestureRecognizer:tapTwice];
      [self.button addGestureRecognizer:tapTrice];
}

【讨论】：