我能够做添加一个“占位符”到UITextView与很多少的代码。这就是我所做的:

UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(60, 800, 200, 60)];
textView.text = @"Write characters here...";
textView.textColor=[UIColor grayColor];
textView.font = [UIFont fontWithName:@"Hevlatica" size:15];
textView.delegate=self;

我猜这不是一个真正的占位符，因为你必须在写之前删除文本，但如果你想要一些更简单的东西，它可能会有帮助。

如果有人需要Swift的解决方案:

添加UITextViewDelegate到类中

var placeHolderText = "Placeholder Text..."

override func viewDidLoad() {
    super.viewDidLoad()
    textView.delegate = self
}

func textViewShouldBeginEditing(textView: UITextView) -> Bool {

    self.textView.textColor = .black

    if(self.textView.text == placeHolderText) {
        self.textView.text = ""
    }

    return true
}

func textViewDidEndEditing(textView: UITextView) {
    if(textView.text == "") {
        self.textView.text = placeHolderText
        self.textView.textColor = .lightGray
    }
}

override func viewWillAppear(animated: Bool) {

    if(currentQuestion.answerDisplayValue == "") {
        self.textView.text = placeHolderText
        self.textView.textColor = .lightGray
    } else {
        self.textView.text = "xxx" // load default text / or stored 
        self.textView.textColor = .black
    }
}

抱歉添加了另一个答案，但我只是拉出了这样的东西，这创建了最接近uitextfield的占位符。

希望这能帮助到一些人。

-(void)textViewDidChange:(UITextView *)textView{
    if(textView.textColor == [UIColor lightGrayColor]){
        textView.textColor  = [UIColor blackColor]; // look at the comment section in this answer
        textView.text       = [textView.text substringToIndex: 0];// look at the comment section in this answer
    }else if(textView.text.length == 0){
        textView.text       = @"This is some placeholder text.";
        textView.textColor  = [UIColor lightGrayColor];
        textView.selectedRange = NSMakeRange(0, 0);
    }
}

-(void)textViewDidChangeSelection:(UITextView *)textView{
    if(textView.textColor == [UIColor lightGrayColor] && (textView.selectedRange.location != 0 || textView.selectedRange.length != 0)){
        textView.selectedRange = NSMakeRange(0, 0);
    }
}

我找到了自己的解决方案

- (void)textViewDidBeginEditing:(UITextView *)textView
{
    if ([textView.text isEqualToString:PLACEHOLDER_TEXT])
    {
        textView.textColor = [UIColor lightGrayColor];
        dispatch_async(dispatch_get_main_queue(), ^
                       {
                           textView.selectedRange = NSMakeRange(0, 0);
                       });
    }
    else
    {
        textView.textColor = [UIColor blackColor];
    }

    [textView becomeFirstResponder];
}

- (void)textViewDidEndEditing:(UITextView *)textView
{
    if ([textView.text isEqualToString:@""])
    {
        textView.text = PLACEHOLDER_TEXT;
        textView.textColor = [UIColor lightGrayColor];
    }

    [textView resignFirstResponder];
}

- (BOOL)textView:(UITextView *)textView
shouldChangeTextInRange:(NSRange)range
 replacementText:(NSString *)text
{
    if (range.location == 0 && range.length == [[textView text] length] && [text isEqualToString:@""])
    {
        textView.text = PLACEHOLDER_TEXT;
        textView.textColor = [UIColor lightGrayColor];

        dispatch_async(dispatch_get_main_queue(), ^
                       {
                           textView.selectedRange = NSMakeRange(0, 0);
                       });

        return NO;
    }

    if ([textView.text isEqualToString:PLACEHOLDER_TEXT])
    {
        textView.text = @"";
        textView.textColor = [UIColor blackColor];
    }

    return YES;
}

这里还有另一种方法，它复制了UITextField占位符的轻微缩进:

将UITextField拖到UITextView的右边，这样它们的左上角就对齐了。将占位符文本添加到文本字段。

在viewDidLoad中添加:

[tView setDelegate:self];
tView.contentInset = UIEdgeInsetsMake(-8,-8,0,0);
tView.backgroundColor = [UIColor clearColor];

然后添加:

- (void)textViewDidChange:(UITextView *)textView {
    if (textView.text.length == 0) {
        textView.backgroundColor = [UIColor clearColor];            
    } else {
        textView.backgroundColor = [UIColor whiteColor];
    }
}

在UITextView中创建占位符是不可能的，但是你可以通过这个生成类似占位符的效果。

  - (void)viewDidLoad{      
              commentTxtView.text = @"Comment";
              commentTxtView.textColor = [UIColor lightGrayColor];
              commentTxtView.delegate = self;

     }
       - (BOOL) textViewShouldBeginEditing:(UITextView *)textView
     {
         commentTxtView.text = @"";
         commentTxtView.textColor = [UIColor blackColor];
         return YES;
     }

     -(void) textViewDidChange:(UITextView *)textView
     {

    if(commentTxtView.text.length == 0){
        commentTxtView.textColor = [UIColor lightGrayColor];
        commentTxtView.text = @"Comment";
        [commentTxtView resignFirstResponder];
    }
    }

或者你可以添加标签在textview就像

       lbl = [[UILabel alloc] initWithFrame:CGRectMake(10.0, 0.0,textView.frame.size.width - 10.0, 34.0)];


[lbl setText:kDescriptionPlaceholder];
[lbl setBackgroundColor:[UIColor clearColor]];
[lbl setTextColor:[UIColor lightGrayColor]];
textView.delegate = self;

[textView addSubview:lbl];

并设置

- (void)textViewDidEndEditing:(UITextView *)theTextView
{
     if (![textView hasText]) {
     lbl.hidden = NO;
}
}

- (void) textViewDidChange:(UITextView *)textView
{
    if(![textView hasText]) {
      lbl.hidden = NO;
}
else{
    lbl.hidden = YES;
 }  
}