//
//TextView+Extension.swift
//Tiger
//
//Created by admin on 15/12/5.
//Copyright © 2015年xidaMM. All rights reserved.
//
importFoundation
//MARK:扩展TextView的placeHolder属性
varkPlaceholderLabelPointer:UInt8=0
extension UITextView{
var placeHolderTextView:UITextView? {
get{
return objc_getAssociatedObject(self,&kPlaceholderLabelPointer)as?UITextView
}
set{
objc_setAssociatedObject(self, &kPlaceholderLabelPointer, newValue,objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
}
funcsetPlaceHolder(placeHolderStr:String) {
ifplaceHolderTextView==nil{
placeHolderTextView=UITextView(frame:self.bounds)
placeHolderTextView?.userInteractionEnabled=false
placeHolderTextView?.text= placeHolderStr
placeHolderTextView?.textColor=UIColor.grayColor()
self.insertSubview(placeHolderTextView!, atIndex:0)
}
}
publicoverridefuncwillMoveToSuperview(newSuperview:UIView?) {
NSNotificationCenter.defaultCenter().addObserver(self,
selector:Selector("_didChange:"),
name:UITextViewTextDidChangeNotification,
object:nil)
}
func_didChange (notification:NSNotification) {
guardplaceHolderTextView!=nilelse{
return
}
ifnotification.object===self{
iftext.lengthOfBytesUsingEncoding(NSUTF8StringEncoding) >0{
placeHolderTextView!.hidden=true
}else{
placeHolderTextView!.hidden=false
}
}
}
}
