swift为UIView添加extension扩展frame

import UIKit

extension UIView {

    // x
    var x : CGFloat {
        
        get {
            
            return frame.origin.x
        }
        
        set(newVal) {
        
            var tmpFrame : CGRect = frame
            tmpFrame.origin.x     = newVal
            frame                 = tmpFrame
        }
    }
    
    // y
    var y : CGFloat {
        
        get {
            
            return frame.origin.y
        }
        
        set(newVal) {
            
            var tmpFrame : CGRect = frame
            tmpFrame.origin.y     = newVal
            frame                 = tmpFrame
        }
    }
    
    // height
    var height : CGFloat {
        
        get {
            
            return frame.size.height
        }
        
        set(newVal) {
            
            var tmpFrame : CGRect = frame
            tmpFrame.size.height  = newVal
            frame                 = tmpFrame
        }
    }
    
    // width
    var width : CGFloat {
        
        get {
            
            return frame.size.width
        }
        
        set(newVal) {
            
            var tmpFrame : CGRect = frame
            tmpFrame.size.width   = newVal
            frame                 = tmpFrame
        }
    }
    
    // left
    var left : CGFloat {
    
        get {
            
            return x
        }
        
        set(newVal) {
            
            x = newVal
        }
    }
    
    // right
    var right : CGFloat {
    
        get {
            
            return x + width
        }
        
        set(newVal) {
            
            x = newVal - width
        }
    }
    
    // top
    var top : CGFloat {
    
        get {
            
            return y
        }
        
        set(newVal) {
            
            y = newVal
        }
    }
    
    // bottom
    var bottom : CGFloat {
    
        get {
            
            return y + height
        }
        
        set(newVal) {
            
            y = newVal - height
        }
    }
    
    var centerX : CGFloat {
    
        get {
            
            return center.x
        }
        
        set(newVal) {
            
            center = CGPoint(x: newVal, y: center.y)
        }
    }
    
    var centerY : CGFloat {
    
        get {
            
            return center.y
        }
        
        set(newVal) {
            
            center = CGPoint(x: center.x, y: newVal)
        }
    }
    
    var middleX : CGFloat {
    
        get {
            
            return width / 2
        }
    }
    
    var middleY : CGFloat {
        
        get {
            
            return height / 2
        }
    }
    
    var middlePoint : CGPoint {
    
        get {
            
           return CGPoint(x: middleX, y: middleY)
        }
    }
}

import UIKit

extension UIView {
    
    //设置随机背景色
    func backgroundColorRandom(){
        
        self.backgroundColor = UIColor(red: CGFloat(CGFloat(random())/CGFloat(RAND_MAX)), green: CGFloat(CGFloat(random())/CGFloat(RAND_MAX)), blue: CGFloat(CGFloat(random())/CGFloat(RAND_MAX)), alpha: 1)
    }
    
    var x : CGFloat!{
        get{
            NSLog("get")
            return self.frame.origin.x
            
        }
        set(newX){
            var rect : CGRect! = self.frame
            rect.origin.x = newX
            self.frame = rect
            NSLog("set")
        }
        
    }
    
    var y : CGFloat!{
        get{
            return self.frame.origin.y
        }
        set(newY){
            var rect : CGRect! = self.frame
            rect.origin.y = newY
            self.frame = rect
        }
        
    }
    
    var width : CGFloat!{
        get{
            return self.frame.size.width
        }
        set(newW){
            var rect : CGRect! = self.frame
            rect.size.width = newW
            self.frame = rect
        }
        
    }
    
    var height : CGFloat!{
        get{
            return self.frame.size.height
        }
        set(newH){
            var rect : CGRect! = self.frame
            rect.size.height = newH
            self.frame = rect
        }
        
    }
    
}