自有 UITextViewDelegate 自动换行

加入UITextViewDelegate

overridefuncviewDidLoad() {

super.viewDidLoad()

// Do any additional setup after loading the view.

//设置UITextView

contentTextView.delegate=self

}

当输入框被改变时

functextViewDidChange(_textView:UITextView) {

lettextStrNum = textView.textasNSString

letViewWidth =Int(contentTextView.frame.width/20)

letlineNum =Int(textStrNum.length/ ViewWidth) +1

iftextStrNum.length>0{

contentTextViewplaceholder.isHidden=true

}else{

contentTextViewplaceholder.isHidden=false

}

if( lineNum <=3){

contentTextViewHeight.constant=105

}else{

contentTextViewHeight.constant=CGFloat(32.5*Double(lineNum))

}

}