如何在我的应用程序中实现 UITapGestureRecognizer [英] How do I implement the UITapGestureRecognizer into my application

问题描述

我对编程和 Objective C 很陌生.我想知道如何制作一个应用程序，它有一个空白屏幕和一个持续一分钟的计时器.你应该尽可能快地点击，尽可能长时间地点击.我想知道如何在我的代码中实现 UITapGestureRecognizer.

I am quite new to programming and Objective C. I was wondering how to make an app which has a blank screen and a timer that goes for one minute. You are meant to tap as fast as you can and as long as you can for. I was wondering how to implement the UITapGestureRecognizer into my code.

推荐答案

这是有关如何在您的班级中实施手势识别器的分步指南:

This is a step by step guide on how to implement gesture recognizers in your class:

1. 使您的类符合 UIGestureRecognizerDelegate 协议.

实例化手势识别器.例如，要实例化一个 UITapGestureRecognizer，我们会这样做:

Instantiate the gesture recognizer. For example, to instantiate a UITapGestureRecognizer, we will do:

UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTapFrom:)];

在这里，action 是处理手势的选择器.在这里，我们的选择器 handleTapFrom 看起来像:

Here, action is the selector which will handle the gesture. Here, our selector handleTapFrom will look something like:

- (void) handleTapFrom: (UITapGestureRecognizer *)recognizer
{
    //Code to handle the gesture
}

选择器的参数是手势识别器.我们可以使用这个手势识别器来访问它的属性，例如，我们可以找到手势识别器的状态，比如，UIGestureRecognizerStateBegan、UIGestureRecognizerStateEnded等

The argument to the selector is the gesture recognizer. We can use this gesture recognizer to access its properties, for example, we can find the state of the gesture recognizer, like, UIGestureRecognizerStateBegan, UIGestureRecognizerStateEnded, etc.

在实例化的手势识别器上设置所需的属性.例如，对于 UITapGestureRecognizer，我们可以设置属性 numberOfTapsRequired 和 numberOfTouchesRequired.

Set the desired properties on the instantiated gesture recognizer. For example, for a UITapGestureRecognizer, we can set the properties numberOfTapsRequired, and numberOfTouchesRequired.

将手势识别器添加到要检测手势的视图中.在我们的示例代码中(我将分享该代码供您参考)，我们将使用以下代码行向 imageView 添加手势识别器:

Add the gesture recognizer to the view you want to detect gestures for. In our sample code (I will be sharing that code for your reference), we will add gesture recognizers to an imageView with the following line of code:

[self.imageView addGestureRecognizer:tapGestureRecognizer];

将手势识别器添加到视图后，设置手势识别器的委托，即处理所有手势识别器的类.在我们的示例代码中，它类似于:

After adding the gesture recognizer to the view, set the delegate for the gesture recognizer, i.e. the class which will handle all the gesture recognizer stuff. In our sample code, it would be like:

tapGestureRecognizer.delegate = self;

注意:在将手势识别器添加到视图后分配代理.否则，不会调用 action 方法.

Note: Assign the delegate after adding the gesture recognizer to the view. Otherwise, the action method won’t be called.

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