How do I size a UITextView to its content?

2018-12-31 02:32发布

Is there a good way to adjust the size of a UITextView to conform to its content? Say for instance I have a UITextView that contains one line of text:

"Hello world"

I then add another line of text:

"Goodbye world"

Is there a good way in Cocoa Touch to get the rect that will hold all of the lines in the text view so that I can adjust the parent view accordingly?

As another example, look at the notes' field for events in the Calendar application - note how the cell (and the UITextView it contains) expands to hold all lines of text in the notes' string.

30条回答
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2楼-- · 2018-12-31 02:39

Hope this helps:

- (void)textViewDidChange:(UITextView *)textView {
  CGSize textSize = textview.contentSize;
  if (textSize != textView.frame.size)
      textView.frame.size = textSize;
}
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无色无味的生活
3楼-- · 2018-12-31 02:39

The Best way which I found out to re-size the height of the UITextView according to the size of the text.

CGSize textViewSize = [YOURTEXTVIEW.text sizeWithFont:[UIFont fontWithName:@"SAMPLE_FONT" size:14.0]
                       constrainedToSize:CGSizeMake(YOURTEXTVIEW.frame.size.width, FLT_MAX)];

or You can USE

CGSize textViewSize = [YOURTEXTVIEW.text sizeWithFont:[UIFont fontWithName:@"SAMPLE_FONT" size:14.0]
                       constrainedToSize:CGSizeMake(YOURTEXTVIEW.frame.size.width, FLT_MAX) lineBreakMode:NSLineBreakByTruncatingTail];
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其实,你不懂
4楼-- · 2018-12-31 02:40

We can do it by constraints .

  1. Set Height constraints for UITextView. enter image description here

2.Create IBOutlet for that height constraint.

 @property (weak, nonatomic) IBOutlet NSLayoutConstraint *txtheightconstraints;

3.don't forget to set delegate for your textview.

4.

-(void)textViewDidChange:(UITextView *)textView
{
    CGFloat fixedWidth = textView.frame.size.width;
    CGSize newSize = [textView sizeThatFits:CGSizeMake(fixedWidth, MAXFLOAT)];
    CGRect newFrame = textView.frame;
    newFrame.size = CGSizeMake(fmaxf(newSize.width, fixedWidth), newSize.height);
    NSLog(@"this is updating height%@",NSStringFromCGSize(newFrame.size));
    [UIView animateWithDuration:0.2 animations:^{
                  _txtheightconstraints.constant=newFrame.size.height;
    }];

}

then update your constraint like this :)

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梦寄多情
5楼-- · 2018-12-31 02:40

Starting with iOS 8, it is possible to use the auto layout features of a UITableView to automatically resize a UITextView with no custom code at all. I have put a project in github that demonstrates this in action, but here is the key:

  1. The UITextView must have scrolling disabled, which you can do programmatically or through the interface builder. It will not resize if scrolling is enabled because scrolling lets you view the larger content.
  2. In viewDidLoad for the UITableViewController, you must set a value for estimatedRowHeight and then set the rowHeight to UITableViewAutomaticDimension.

- (void)viewDidLoad {
    [super viewDidLoad];
    self.tableView.estimatedRowHeight = self.tableView.rowHeight;
    self.tableView.rowHeight = UITableViewAutomaticDimension;
}
  1. The project deployment target must be iOS 8 or greater.
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刘海飞了
6楼-- · 2018-12-31 02:42

This no longer works on iOS 7 or above

There is actually a very easy way to do resizing of the UITextView to its correct height of the content. It can be done using the UITextView contentSize.

CGRect frame = _textView.frame;
frame.size.height = _textView.contentSize.height;
_textView.frame = frame;

One thing to note is that the correct contentSize is only available after the UITextView has been added to the view with addSubview. Prior to that it is equal to frame.size

This will not work if auto layout is ON. With auto layout, the general approach is to use the sizeThatFits method and update the constant value on a height constraint.

CGSize sizeThatShouldFitTheContent = [_textView sizeThatFits:_textView.frame.size];
heightConstraint.constant = sizeThatShouldFitTheContent.height;

heightConstraint is a layout constraint that you typically setup via a IBOutlet by linking the property to the height constraint created in a storyboard.


Just to add to this amazing answer, 2014, if you:

[self.textView sizeToFit];

there is a difference in behaviour with the iPhone6+ only:

enter image description here

With the 6+ only (not the 5s or 6) it does add "one more blank line" to the UITextView. The "RL solution" fixes this perfectly:

CGRect _f = self.mainPostText.frame;
_f.size.height = self.mainPostText.contentSize.height;
self.mainPostText.frame = _f;

It fixes the "extra line" problem on 6+.

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笑指拈花
7楼-- · 2018-12-31 02:42

I reviewed all the answers and all are keeping fixed width and adjust only height. If you wish to adjust also width you can very easily use this method:

so when configuring your text view, set scroll disabled

textView.isScrollEnabled = false

and then in delegate method func textViewDidChange(_ textView: UITextView) add this code:

func textViewDidChange(_ textView: UITextView) {
    let newSize = textView.sizeThatFits(CGSize(width: CGFloat.greatestFiniteMagnitude, height: CGFloat.greatestFiniteMagnitude))
    textView.frame = CGRect(origin: textView.frame.origin, size: newSize)
}

Outputs:

enter image description here

enter image description here

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