获取Swift中多个触摸的坐标 [英] Get coordinates of multiple touches in Swift

问题描述

所以我一直在试图获取屏幕上的触摸坐标。到目前为止，我可以得到一个触摸的坐标：

 覆盖func touchesBegan（触摸：NSSet，withEvent事件：UIEvent） {
让touch = touches.anyObject（）！作为UITouch 
让location = touch.locationInView（self.view）
 println（location）
} 
  

但是当用两根手指触摸时，我只得到第一次触摸的坐标。多点触控工作（我使用这个小教程测试：

否则你总是只需触摸 touchesBegan （请参阅此处的文档）。

然后，在内搜索touchBegan ，迭代一组触摸以获得它们的坐标：

 覆盖func touchesBegan（_ touches：Set< ; UITouch>，有事件：UIEvent？）{
触摸触摸{
 let location = touch.location（in：self.view）
 print（location）
} 
} 
  

So I've been messing around trying to get the coordinates of touches on the screen. So far I can get the coordinates of one touch with this:

override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {
    let touch = touches.anyObject()! as UITouch
    let location = touch.locationInView(self.view)
    println(location)
}

But when touching with two fingers I only get the coordinates of the first touch. Multi-touch works (I tested with this little tutorial: http://www.techotopia.com/index.php/An_Example_Swift_iOS_8_Touch,_Multitouch_and_Tap_Application). So my question is, how do I get the coordinates of the second (and third, fourth...) touch?

解决方案

** Updated to Swift 4 and Xcode 9 (8 Oct 2017) **

First of all, remember to enable multi-touch events by setting

self.view.isMultipleTouchEnabled = true

in your UIViewController's code, or using the appropriate storyboard option in Xcode:

Otherwise you'll always get a single touch in touchesBegan (see documentation here).

Then, inside touchesBegan, iterate over the set of touches to get their coordinates:

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    for touch in touches {
        let location = touch.location(in: self.view)
        print(location)
    }
}

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