問題描述

我嘗試了許多不同的方法來實現擴展圖像和捏拉縮放.我找到了有關如何使用項目中保存的圖像執行此操作的教程，但是我正在從 Firebase 檢索我的圖像.我希望一張圖片占據 ProfileViewController 屏幕的一半左右，而其他圖片能夠擴展整頁并且能夠縮放.我現在擁有的代碼可以做到這一點，但是縮放和位置不干凈或易于使用.

I have tried many different ways of implementing expand image and pinch to zoom. I have found tutorials on how to do this with images saved in my project however I am retrieving my images from Firebase. I would like one image to take about half the ProfileViewController screen and the other pictures to be able to be expanded full page and also have the ability to zoom. My code I have for it now does this however the zooming and the position is not clean or easy to use.

var newImageView: UIImageView!



@IBAction func imageTapped(_ sender: UITapGestureRecognizer)  {
    let imageView = sender.view as! UIImageView

    let scrollView = UIScrollView(frame: self.view.frame)


    newImageView = UIImageView(image: imageView.image)
    newImageView.frame = self.view.frame
    newImageView.backgroundColor = .black
    newImageView.contentMode = .top
    newImageView.isUserInteractionEnabled = true


    let tap = UITapGestureRecognizer(target: self, action: #selector(dismissFullscreenImage))
    scrollView.addGestureRecognizer(tap)


    scrollView.delegate = self
    scrollView.minimumZoomScale = 1.0
    scrollView.maximumZoomScale = 3.0

    scrollView.addSubview(newImageView)

    self.view.addSubview(scrollView)
}

func viewForZooming(in scrollView: UIScrollView) -> UIView?
{
    return newImageView;
}

func dismissFullscreenImage(_ sender: UITapGestureRecognizer) {
    sender.view?.removeFromSuperview()
}

推薦答案

這是我正在以編程方式創建滾動視圖和圖像視圖，這里 img 是我正在選擇的 PHAsset圖片來自畫廊.

Here is I am creating scrollview and imageview programatically and here img is a PHAsset that I am selecting image from gallery.

我在做什么，選擇一個圖像并移動到其他視圖控制器，然后我根據我的 imageview 調整該圖像的大小因此圖像在縮放后不會模糊.

最小縮放受限于 imageview，最大縮放為 4.0.

Here what I am doing, select an image and move to other view controller and I resize that image according to my imageview So image is not blurry after zooming it.

Minimum zooming is imageview bound and maxmimum zooming is 4.0.

func singleVC1()  {
        let v = UIView(frame: CGRect(x: 40, y: 50, width: self.view.frame.size.width - 80, height: view.frame.size.height - 200))
        let view1 = UIView(frame: CGRect(x: 0, y: 0, width: v.frame.size.width, height: v.frame.size.height/2 - 1))
        let scroll1 = UIScrollView.init(frame: view1.bounds)
        let imgview = UIImageView.init(frame: (CGRect)(origin: CGPoint.zero, size: self.returnAspectSize(targetWidth: view.frame.size.width, img: img)))
        self.setZoomScale(scrollview: scroll1, imageview: imgview)
        imgview.image = self.getUIImage(asset: img)
        scroll1.maximumZoomScale = 4.0;
        scroll1.delegate = self;
        scroll1.bounces = false
        scroll1.contentSize =  imgview.frame.size
        scroll1.addSubview(imgview)
        view1.layer.borderColor = UIColor.red.cgColor
        view1.layer.borderWidth = 5.0
        view1.addSubview(scroll1)
        v.addSubview(view1)

        let view2 = UIView(frame: CGRect(x: 0, y: v.frame.size.height/2+1, width: v.frame.size.width, height: v.frame.size.height/2 - 1))
        let scroll2 = UIScrollView.init(frame: view2.bounds)
        let imgview1 = UIImageView.init(frame: (CGRect)(origin: CGPoint.zero, size: self.returnAspectSize(targetWidth: view.frame.size.width, img: img)))
        imgview1.image = self.getUIImage(asset: img)
        self.setZoomScale(scrollview: scroll2, imageview: imgview1)
        scroll2.bounces = false

        scroll2.maximumZoomScale = 4.0;
        scroll2.delegate = self;
        view2.layer.borderColor = UIColor.red.cgColor
        view2.layer.borderWidth = 5.0
        scroll2.contentSize = imgview1.frame.size
        scroll2.addSubview(imgview1)
        view2.addSubview(scroll2)
        v.addSubview(view2)
        self.view.addSubview(v)
    }
func setZoomScale(scrollview : UIScrollView, imageview : UIImageView) {
        var minZoom = min(self.view.bounds.size.width / imageview.bounds.size.width, self.view.bounds.size.height / imageview.bounds.size.height);

        if (minZoom > 1.0) {
            minZoom = 1.0;
        }
        scrollview.minimumZoomScale = minZoom;
        scrollview.zoomScale = minZoom;
    }
    func returnAspectSize(targetWidth : CGFloat, img : PHAsset) -> CGSize {
        let img1 = self.getUIImage(asset: self.img)
        let targetwidth = targetWidth
        let scalefactor = (CGFloat)(targetwidth) / (CGFloat)((img1?.size.width)!)
        let targetheight = (img1?.size.height)! * scalefactor
        let targesize = CGSize(width: (CGFloat)(targetwidth), height: targetheight)
        return targesize
    }

試試這個.我相信這會對你有所幫助.

Try this. I am sure this will help you.

這篇關于UIImageView 在 UIScrollView 中縮放和捏合的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！