如何:将视图放在前面；设置最大/最小捏合手势比例；将屏幕限制设置为平移手势 [英] How to: bring view to front on tap; set max/min pinch gesture scale; set screen limit to pan gesture

问题描述

注意:我发现的所有东西都太旧了，或者与我实际需要的东西相差太大，而且我尝试了几乎所有我发现的东西，但没有一种方法是正确的.

我创建了 3 个 UIView，我可以拖动它们并缩放它们.现在，我需要:

1. 将其中一些放在前面:我想为每个添加一个UITapGesture 允许我将点击的 UIView 带到前面将其他 UIViews 传递到后面；
2. 为 UIPinchGestureRecognizer 设置最大/最小比例，以便我不能有超大的 UIiews 或微小的 UIViews；
3. 为 UIPanGestureRecognizer 设置一种屏幕限制，以便我不能将我的 UIViews 拖到主视图之外.

这是我的代码:

https://github.com/marybnq/Views

解决方案

我解决了我的问题！

<块引用>

1. 我想出了如何为 UIPinchGestureRecognizer 设置最大/最小比例，这就是我所做的.

 变量识别器Scale:CGFloat = 1.0var maxScale:CGFloat = 1.5var minScale:CGFloat = 0.8@IBAction func handlePinch(_ pinchGesture: UIPinchGestureRecognizer) {守卫 pinchGesture.view != nil else {return}如果 pinchGesture.state == .began ||pinchGesture.state == .changed{if (recognizerScale < maxScale && pinchGesture.scale > 1.0) {pinchGesture.view?.transform = (pinchGesture.view?.transform)!.scaledBy(x: pinchGesture.scale, y: pinchGesture.scale)识别器刻度 *= pinchGesture.scalepinchGesture.scale = 1.0}if (recognizerScale > minScale && pinchGesture.scale <1.0) {pinchGesture.view?.transform = (pinchGesture.view?.transform)!.scaledBy(x: pinchGesture.scale, y: pinchGesture.scale)识别器刻度 *= pinchGesture.scalepinchGesture.scale = 1.0}}}

<块引用>

2. 为了将视图置于最前面，我创建了多个 UIPanGestureRecognizers 并添加了 combineSubviewToFront:

 @IBAction func handlePan1(recognizer:UIPanGestureRecognizer) {让翻译=recognizer.translation(in: self.view)如果让视图 = 识别器.视图 {view.center = CGPoint(x:view.center.x + translation.x,y:view.center.y + translation.y)}view.bringSubviewToFront(view1)识别器.setTranslation(CGPoint.zero, in: self.view)}@IBAction func handlePan2(recognizer:UIPanGestureRecognizer) {让翻译=recognizer.translation(in: self.view)如果让视图 = 识别器.视图 {view.center = CGPoint(x:view.center.x + translation.x,y:view.center.y + translation.y)}view.bringSubviewToFront(view2)识别器.setTranslation(CGPoint.zero, in: self.view)}

ecc...但是，如果您也想限制平移手势，则无法执行此操作，因此您可能需要添加一个点击手势识别器:

向您的视图添加一个gestureRecognizer并设置代理.

@IBAction func tappedView1(recognizer: UITapGestureRecognizer) {view.bringSubviewToFront(myView)}

在您的视图中DidLoad:

 let tap = UITapGestureRecognizer(target: self, action: #selector(tappedView1))tap.cancelsTouchesInView = falseself.view.addGestureRecognizer(点击)

<块引用>

3. 要设置屏幕限制/平移限制，我找到了以下代码:

@IBAction func handlePan(recognizer:UIPanGestureRecognizer) {让翻译=recognizer.translation(in: self.view)让 statusFrame = UIApplication.shared.statusBarFrame如果让receiverView =receiver.view {如果receiverView.frame.origin.x <0.0 {识别视图.frame.origin = CGPoint(x:0.0，y:识别视图.frame.origin.y)}如果receiverView.frame.origin.y 

NB: everything I found is too old or way too different from what I actually need, also I tried almost everything I found and nothing worked the right way.

I created 3 UIViews, I can drag them around and zoom them. Now, I need to:

1. Bring some of them to the front: I want to add to each of them an UITapGesture that allows me to bring the tapped UIView to the front passing the other UIViews to the back;
2. Set a max/ min scale for the UIPinchGestureRecognizer so that I can't have super large UIiews or tiny UIViews;
3. Set a sort of screen limit to the UIPanGestureRecognizer so that I can't drag my UIViews outside of the main view.

Here's my code:

https://github.com/marybnq/Views

解决方案

I solved my problem!

1. I figured out how to set a max/ min scale for the UIPinchGestureRecognizer, here's what I did.

    var recognizerScale:CGFloat = 1.0
    var maxScale:CGFloat = 1.5
    var minScale:CGFloat = 0.8

    @IBAction func handlePinch(_ pinchGesture: UIPinchGestureRecognizer) {
        guard pinchGesture.view != nil else {return}

        if pinchGesture.state == .began || pinchGesture.state == .changed{
            if (recognizerScale < maxScale && pinchGesture.scale > 1.0) {
                pinchGesture.view?.transform = (pinchGesture.view?.transform)!.scaledBy(x: pinchGesture.scale, y: pinchGesture.scale)
                recognizerScale *= pinchGesture.scale
                pinchGesture.scale = 1.0
            }
            if (recognizerScale > minScale && pinchGesture.scale < 1.0) {
                pinchGesture.view?.transform = (pinchGesture.view?.transform)!.scaledBy(x: pinchGesture.scale, y: pinchGesture.scale)
                recognizerScale *= pinchGesture.scale
                pinchGesture.scale = 1.0
            }
        }
    }

2. In order to bring views to the front I created multiple UIPanGestureRecognizers and I added bringSubviewToFront:

     @IBAction func handlePan1(recognizer:UIPanGestureRecognizer) {
        let translation = recognizer.translation(in: self.view)
        if let view = recognizer.view {
            view.center = CGPoint(x:view.center.x + translation.x,
                                  y:view.center.y + translation.y)
        }
        view.bringSubviewToFront(view1)
        recognizer.setTranslation(CGPoint.zero, in: self.view)
    }

     @IBAction func handlePan2(recognizer:UIPanGestureRecognizer) {
        let translation = recognizer.translation(in: self.view)
        if let view = recognizer.view {
            view.center = CGPoint(x:view.center.x + translation.x,
                                  y:view.center.y + translation.y)
        }
        view.bringSubviewToFront(view2)
        recognizer.setTranslation(CGPoint.zero, in: self.view)
    }

ecc... BUT you can't do this if you want to limit the pan gesture as well, so you might want to add a tap gestureRecognizer instead:

Add a gestureRecognizer to your view and set the delegate.

@IBAction func tappedView1(recognizer: UITapGestureRecognizer) {
        view.bringSubviewToFront(myView)
    }

In your viewDidLoad:

 let tap = UITapGestureRecognizer(target: self, action: #selector(tappedView1))
        tap.cancelsTouchesInView = false
        self.view.addGestureRecognizer(tap)

3. To set a screen limit/ pan limit, I found this code:

@IBAction func handlePan(recognizer:UIPanGestureRecognizer) {
        let translation = recognizer.translation(in: self.view)
        let statusFrame = UIApplication.shared.statusBarFrame


        if let recognizerView = recognizer.view {
            if recognizerView.frame.origin.x < 0.0 {
                recognizerView.frame.origin = CGPoint(x: 0.0, y: recognizerView.frame.origin.y)
            }
            if recognizerView.frame.origin.y < statusFrame.height {
                recognizerView.frame.origin = CGPoint(x: recognizerView.frame.origin.x, y: statusFrame.height)
            }
            if recognizerView.frame.origin.x + recognizerView.frame.size.width > view.frame.width {
                recognizerView.frame.origin = CGPoint(x: view.frame.width - recognizerView.frame.size.width, y: recognizerView.frame.origin.y)

            }
            if recognizerView.frame.origin.y + recognizerView.frame.size.height > view.frame.height {
                recognizerView.frame.origin = CGPoint(x: recognizerView.frame.origin.x, y: view.frame.height - recognizerView.frame.size.height)
            }
        }

        if let centerX = recognizer.view?.center.x, let centerY = recognizer.view?.center.y {
            recognizer.view?.center = CGPoint.init(x: centerX + translation.x , y: centerY + translation.y)
            recognizer.setTranslation(CGPoint.zero, in: self.view)
        }

        view.bringSubviewToFront(view1)
        recognizer.setTranslation(CGPoint.zero, in: self.view)
}

这篇关于如何:将视图放在前面；设置最大/最小捏合手势比例；将屏幕限制设置为平移手势的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！