对于iOS 7.0，不是将frame.size.height设置为contentSize. height。使用[textView sizeToFit]。

看这个问题。

看起来这个家伙为NSTextView找到了答案，他的答案也适用于iOS。事实证明，intrinsicContentSize并不与布局管理器同步。如果一个布局发生在intrinsicContentSize之后，你可能会有一个差异。

他有一个简单的解决办法。

NSOutlineView中的NSTextView与IntrinsicContentSize设置错误的高度

这工作得很好，当我需要使文本在一个UITextView适合一个特定的区域:

// The text must already be added to the subview, or contentviewsize will be wrong.

- (void) reduceFontToFit: (UITextView *)tv {
    UIFont *font = tv.font;
    double pointSize = font.pointSize;

    while (tv.contentSize.height > tv.frame.size.height && pointSize > 7.0) {
        pointSize -= 1.0;
        UIFont *newFont = [UIFont fontWithName:font.fontName size:pointSize];
        tv.font = newFont;
    }
    if (pointSize != font.pointSize)
        NSLog(@"font down to %.1f from %.1f", pointSize, tv.font.pointSize);
}

The easiest way to ask a UITextView is just calling -sizeToFitit should work also with scrollingEnabled = YES, after that check for the height and add a height constraint on the text view with the same value. Pay attention that UITexView contains insets, this means that you can't ask the string object how much space it want to use, because this is just the bounding rect of the text. All the person that are experiencing wrong size using -sizeToFit it's probably due to the fact that the text view has not been layout yet to the interface size. This always happen when you use size classes and a UITableView, the first time cells are created in the - tableView:cellForRowAtIndexPath: the comes out with the size of the any-any configuration, if you compute you value just now the text view will have a different width than the expected and this will screw all sizes. To overcome this issue I've found useful to override the -layoutSubviews method of the cell to recalculate textview height.

更新

你需要做的关键事情是关闭UITextView中的滚动。

myTextView.scrollEnabled = @NO

原来的答案

要在UITableViewCell中创建一个动态大小的UITextView，我发现以下组合在Xcode 6和iOS 8 SDK中有效:

Add a UITextView to a UITableViewCell and constrain it to the sides Set the UITextView's scrollEnabled property to NO. With scrolling enabled, the frame of the UITextView is independent of its content size, but with scrolling disabled, there is a relationship between the two. If your table is using the original default row height of 44 then it will automatically calculate row heights, but if you changed the default row height to something else, you may need to manually switch on auto-calculation of row heights in viewDidLoad: tableView.estimatedRowHeight = 150; tableView.rowHeight = UITableViewAutomaticDimension;

对于只读动态大小的uitextview，就是这样。如果你允许用户在你的UITextView中编辑文本，你还需要:

实现UITextViewDelegate协议的textViewDidChange:方法，并告诉tableView在每次文本被编辑时重新绘制自己: - (void)textViewDidChange:(UITextView *)textView; ｛ [tableView beginUpdates]; [tableView endUpdates]; ｝ 别忘了在某个地方设置UITextView委托，在Storyboard或者tableView:cellForRowAtIndexPath:

在ios 11上非常有效 我在一个牢房里工作，就像一个有泡泡的聊天室。

let content = UITextView(frame: CGRect(x: 4, y: 4, width: 0, height: 0))
content.text = "what ever short or long text you wanna try"
content.textAlignment = NSTextAlignment.left
content.font = UIFont.systemFont(ofSize: 13)
let spaceAvailable = 200 //My cell is fancy I have to calculate it...
let newSize = content.sizeThatFits(CGSize(width: CGFloat(spaceAvailable), height: CGFloat.greatestFiniteMagnitude))
content.isEditable = false
content.dataDetectorTypes = UIDataDetectorTypes.all
content.isScrollEnabled = false
content.backgroundColor = UIColor.clear
bkgView.addSubview(content)