self.bottomTextView.placeholder=@"textView增加placeholder以及设置颜色,自动适应键盘展开和收起。";//设置placeholderself.bottomTextView.placeholderColor=[UIColorpurpleColor];//设置placeholderColorself.bottomTextView.font=[UIFontsystemFontOfSize:16];self.bottomTextView.borderColor=[UIColororangeColo