在 tapGesture 操作选择器中包含协议功能 - iOS Swift [英] Including protocol function in tapGesture action selector - iOS Swift

问题描述

我有一个类 (FilterBar.swift) 和一个视图控制器.viewcontroller 调用该类以使用图像列表填充 scrollView 对象，并且每个图像都添加了一个 tapGestureRecognizer，如下所示:

I have a class (FilterBar.swift) and a viewcontroller. the viewcontroller calls the class to populate a scrollView object with list of images and each image has a tapGestureRecognizer added to it as follows:

        let tapGesture = UITapGestureRecognizer(
                        target: imgView, action: Selector("filterClicked:"));
        tapGesture.numberOfTapsRequired = 1;
        tapGesture.numberOfTouchesRequired = 1;
        imgView.addGestureRecognizer(tapGesture);

而且我在 FilterBar 中也有一个函数，如下所示:

and i have a function also in FilterBar as follows:

    @objc func filterClicked(sender: UITapGestureRecognizer) {
    print(sender.view?.superview?.description)
    print("sent from view: \(sender.view!.tag)");
}

当我尝试单击图像时，出现以下错误:

when i attempt to click on the image i get the following error:

2016-03-16 02:06:45.800 ImageFilter[71811:6885004] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIImageView delegate.filterClicked:]: unrecognized selector sent to instance 0x7fc07951f010'

所以我想我可能需要一个协议，所以我在 FilterBar 中创建了一个协议，如下所示:

So i thought maybe i need a protocol, so i created a protocol in FilterBar as follows:

protocol FilterClickedDelegate {
    func filterClicked(sender: UITapGestureRecognizer);
}

let delegate:FilterClickedDelegate?

(adjusted this line) let tapGesture = UITapGestureRecognizer(
             target: imgView, action: Selector("delegate.filterClicked:"));

我将该协议添加到 viewcontroller 类中，并且我还添加了协议所需的功能，但我仍然遇到相同的错误.所以第一个问题:我在这个场景中使用协议是否正确，因为它在视图控制器上运行?

i added that protocol to the viewcontroller class, and i also added the function the protocol needs but i still get the same error. So first question: Am i right to use a protocol in this senario since this is running on viewcontroller?

第二个问题:我在选择器中做错了什么?有没有具体的方法可以在选择器中提及协议函数?

second question: what am i doing wrong in the selector? is there a specific way to mention a protocol function in the selector?

推荐答案

我想通了，在目标部分初始化 UITapGestureRecognizer 时，您需要使用 viewcontroller，它实际上是委托人的委托.所以:

I figured it out, in the target section when initializing the UITapGestureRecognizer you need to use the viewcontroller which is actually the delegate of the delegator. so:

let tapGesture = UITapGestureController(target: vc, action:"filterClicked:");

谢谢大家，希望这能帮助其他陷入同一问题的人！

Thanks all, and hope this will help others stuck on the same issue!

干杯！

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