UITextView*textView = [[UITextViewalloc] initWithFrame:CGRectMake(20,100, [UIScreenmainScreen].bounds.size.width-20,120];
[textView setBackgroundColor:[UIColor greenColor]];
[self.view addSubview:textView];
UILabel*placeHolderLabel = [[UILabelalloc] init];
placeHolderLabel.text =@"请输入建议或意见";
placeHolderLabel.numberOfLines =0;
placeHolderLabel.textColor = [UIColorlightGrayColor];
[placeHolderLabel sizeToFit];
[textView addSubview:placeHolderLabel];
fonttextView.font = [UIFontsystemFontOfSize:12];
placeHolderLabel.font = [UIFontsystemFontOfSize:12];
[textView setValue:placeHolderLabel forKey:@"_placeholderLabel"];
