在OC中我们通过类目Category做UIView属性宽展，方便我们获取常用属性，（x、y、宽、高等）
在Swift中我们也一样可以通过extension来宽展属性
直接上代码，很容易明白
extension UIView{
var x:CGFloat{
get{
return self.frame.origin.x
}
set(newVal){
var temF :CGRect = frame
temF.origin.x = newVal
frame = temF
}
}
var y:CGFloat{
get{
return self.frame.origin.y
}
set(newVal){
var temF :CGRect = frame
temF.origin.y = newVal
frame = temF
}
}
var size:CGSize{
get{
return self.frame.size
}
set(newVal){
var temF :CGRect = frame
temF.size = newVal
frame = temF
}
}
var width:CGFloat{
get{
return self.bounds.width
}
set(newVal){
var temF :CGRect = frame
temF.size.width = newVal
frame = temF
}
}
var height:CGFloat{
get{
return self.bounds.height
}
set(newVal){
var temF :CGRect = frame
temF.size.height = newVal
frame = temF
}
}
}
