UITapGestureRecognizer initWithTarget:action:接受参数的方法? [英] UITapGestureRecognizer initWithTarget:action: method to take arguments?

问题描述

我正在使用UITapGestureRecognizer，因为我正在使用UIScrollView作为我的UILabel的容器.基本上我正在尝试使用带有参数的操作方法，以便例如将myLabel.tag值发送到action方法，以根据要通过轻击触发的UILabel知道要执行什么操作.

I'm using UITapGestureRecognizer because I'm using a UIScrollView that acts as a container for my UILabels. Basically I'm trying to use an action method with arguments so I can e.g. send myLabel.tag value to the action method to know what action to take depending on what UILabel has has been triggered by a tap.

一种实现方法是拥有与UILabel一样多的动作方法，但这并不是十分漂亮"的代码方式.我想要实现的只是使用带switch语句的一种操作方法.

One way of doing it is having as many action methods as UILabels but that isn't very "pretty" codewise. What I would like to achieve is just having one action method with switch statements.

这是可能的还是我必须这样做(叹气):

Is this possible or will I have to do it like this (sigh):

UITapGestureRecognizer *myLabel1Tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(myLabel1Tap)];
[myLabel1Tap addGestureRecognizer:myLabel1Tap];

UITapGestureRecognizer *myLabel2Tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(myLabel2Tap)];
[myLabel1Tap addGestureRecognizer:myLabel2Tap];

UITapGestureRecognizer *myLabelNTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(myLabelNTap)];
[myLabel1Tap addGestureRecognizer:myLabelNTap];

- (void)myLabel1Tap {
// Perform action
}

- (void)myLabel2Tap {
// Perform action
}

- (void)myLabelNTap {
// Perform action
}

推荐答案

向视图添加一个手势识别器，该识别器是您各种标签的超级视图:

Add a single gesture recognizer to the view that is the superview of your various labels:

UITapGestureRecognizer *myLabelTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(myLabelTapHandler:)];
[myLabelParent addGestureRecognizer:myLabelTap];

然后在处理手势时，确定点击了哪个标签:

Then when you handle the gesture, determine which label was tapped:

-(void)myLabelTapHandler:(UIGestureRecognizer *)gestureRecognizer {
    UIView *tappedView = [gestureRecognizer.view hitTest:[gestureRecognizer locationInView:gestureRecognizer.view] withEvent:nil];

    // do something with it
}

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