iOS之仿支付宝刮奖

现在在学swift,之前说要和大家分享的小demo就是这个了,demo本身很简单,由于初学swift,可能有些代码写的不够规范,也请大家多多指教。。。

先看看效果图吧

实现起来也很简单,ui上没什么好说了,注意的一点就是要将image的isUserInteractionEnabled勾打上。实现上是先声明一个变量，判断触摸的是否是需要响应触摸事件的View,然后就是利用UIView的触摸事件,下面是代码

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        for touch:AnyObject in touches {
            let t:UITouch = touch as! UITouch
            if t.view == myImage {
                isTouch = true;
            }
        }
    }
    
    override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
        
        if isTouch == true {
            
            for touch:AnyObject in touches {
                
                UIGraphicsBeginImageContext(myImage.frame.size)
                myImage.image?.draw(in: myImage.bounds)
                let t:UITouch = touch as! UITouch
                let point = t.location(in: t.view)
                let rect = CGRect(x:point.x - 10 ,y:point.y - 10, width: 20, height: 20)
                UIGraphicsGetCurrentContext()!.clear(rect)
                myImage.image = UIGraphicsGetImageFromCurrentImageContext()
                UIGraphicsEndImageContext()
            }
        }
    }
    
    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
        isTouch = false
    }

是不是很简单,有不明白的也可以看Demo,欢迎大家Star.

版权声明：本文为 Crazy Steven 原创出品，欢迎转载，转载时请注明出处！