textView设置placeholder

_textView.delegate = self;
_textView.font = [UIFont systemFontOfSize:15];
_textView.text = @"用的不爽?说两句..";
_textView.textColor = [UIColor lightGrayColor];
_textView.returnKeyType = UIReturnKeyDone;

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
if ([@"\n" isEqualToString:text] == YES)
{
[textView resignFirstResponder];

return NO;
}
return YES;
}
- (void)textViewDidBeginEditing:(UITextView *)textView
{
if ([textView.text isEqualToString:@"用的不爽?说两句.."]) {
textView.text = @"";
}

}
- (void)textViewDidEndEditing:(UITextView *)textView
{
if ([textView.text isEqualToString:@""]) {
textView.text = @"用的不爽?说两句..";
}

}