寫在前面
圖片擦除功能，也是運用圖片的繪製功能，
將圖片繪製後，拿到相應的圖片。當然，有一漲底圖更明顯所有功能演示
實現代碼如下
/**
** 用手勢擦除圖片
- imageView --傳圖片
- bgView --截圖背景
*/
public func clearImage(imageView: UIImageView?, rect: CGRect) -> UIImage? {
if imageView == nil {
return nil
}
//開啓一個位圖上下文
UIGraphicsBeginImageContextWithOptions((imageView?.bounds.size)!, false, 0.0)
//把ImageView內容渲染到上下文當中
let imageCtx = UIGraphicsGetCurrentContext()
imageView?.layer.render(in: imageCtx!)
//擦除上下文當中某一塊區域
imageCtx!.clear(rect)
//得到新圖片
let newImage = UIGraphicsGetImageFromCurrentImageContext()
//關閉上下文
UIGraphicsEndImageContext()
return newImage
}
### 當然你也可以把圖片繪製過程放入子線程中，再次就不列舉了具體用法
//底部圖片
private lazy var bottomImageView: UIImageView = {
let imageView = UIImageView()
imageView.image = UIImage(named: "image")
imageView.frame = CGRect(x: 0, y: 100, width: width, height: width)
self.view.addSubview(imageView)
imageView.isUserInteractionEnabled = true
return imageView
}()
//要擦除的圖片
private lazy var clearImageView: UIImageView = {
let imageView = UIImageView()
imageView.image = UIImage(named: "logo")
imageView.frame = CGRect(x: 0, y: 100, width: width, height: width)
imageView.isUserInteractionEnabled = true
self.view.addSubview(imageView)
return imageView
}()
override func viewDidLoad() {
super.viewDidLoad()
self.view.backgroundColor = UIColor.white
self.bottomImageView.isUserInteractionEnabled = false
let pan = UIPanGestureRecognizer(target: self, action: #selector(DDGClearImageView.clearPan(pan:)))
self.clearImageView.addGestureRecognizer(pan)
}
@objc func clearPan(pan: UIPanGestureRecognizer) {
//獲取當前手指的點
let imageView = pan.view as! UIImageView
let clearPan = pan.location(in: imageView)
//擦除區域的大小
let rect = CGRect(x: clearPan.x - 15, y: clearPan.y - 15, width: 30, height: 30)
let newImage = DDGManage.share.clearImage(imageView: imageView, rect: rect)
imageView.image = newImage
}
### 是不是很好用結束語
此代碼已經上傳到githup[DDGScreenShot](https://github.com/dudongge/DDGScreenShot)
[link](https://github.com/dudongge/DDGScreenShot)
當然這只是這個庫的功能的一小部分
想看更多功能，可以去github上下載，如果對您有幫助，希望您不吝給個star.歡迎查看DDGScreenShot