非常容易工作的解决方案使用代码和故事板。

通过代码

textView.scrollEnabled = false

通过故事板

取消选中“滚动启用”

除此之外什么都不用做。

这个方法似乎适用于ios7

 // Code from apple developer forum - @Steve Krulewitz, @Mark Marszal, @Eric Silverberg
- (CGFloat)measureHeight
{
    if ([self respondsToSelector:@selector(snapshotViewAfterScreenUpdates:)])
    {
    CGRect frame = internalTextView.bounds;
    CGSize fudgeFactor;
    // The padding added around the text on iOS6 and iOS7 is different.
    fudgeFactor = CGSizeMake(10.0, 16.0);

    frame.size.height -= fudgeFactor.height;
    frame.size.width -= fudgeFactor.width;

    NSMutableAttributedString* textToMeasure;
    if(internalTextView.attributedText && internalTextView.attributedText.length > 0){
        textToMeasure = [[NSMutableAttributedString alloc] initWithAttributedString:internalTextView.attributedText];
    }
    else{
        textToMeasure = [[NSMutableAttributedString alloc] initWithString:internalTextView.text];
        [textToMeasure addAttribute:NSFontAttributeName value:internalTextView.font range:NSMakeRange(0, textToMeasure.length)];
    }

    if ([textToMeasure.string hasSuffix:@"\n"])
    {
        [textToMeasure appendAttributedString:[[NSAttributedString alloc] initWithString:@"-" attributes:@{NSFontAttributeName: internalTextView.font}]];
    }

    // NSAttributedString class method: boundingRectWithSize:options:context is
    // available only on ios7.0 sdk.
    CGRect size = [textToMeasure boundingRectWithSize:CGSizeMake(CGRectGetWidth(frame), MAXFLOAT)
                                              options:NSStringDrawingUsesLineFragmentOrigin
                                              context:nil];

    return CGRectGetHeight(size) + fudgeFactor.height;
}
else
{
    return self.internalTextView.contentSize.height;
}
}

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。

这适用于iOS 6.1和iOS 7:

- (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);
    textView.frame = newFrame;
}

或在Swift(适用于Swift 4.1在iOS 11)

let fixedWidth = textView.frame.size.width
let newSize = textView.sizeThatFits(CGSize(width: fixedWidth, height: CGFloat.greatestFiniteMagnitude))
textView.frame.size = CGSize(width: max(newSize.width, fixedWidth), height: newSize.height)

如果你想要支持iOS 6.1，那么你还应该:

textview.scrollEnabled = NO;

我回顾了所有的答案，所有都保持固定的宽度和调整只有高度。如果你想调整宽度，你可以很容易地使用这个方法:

当配置文本视图时，将滚动设置为禁用

textView.isScrollEnabled = false

然后在委托方法func textViewDidChange(_ textView: UITextView)添加以下代码:

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

输出:

不知道为什么人们总是把事情复杂化: 下面就是:

- (void)textViewDidChange:(UITextView *)textView{ CGRect frame = textView.frame;
CGFloat height = [self measureHeightOfUITextView:textView];
CGFloat insets = textView.textContainerInset.top + textView.textContainerInset.bottom;
height += insets;
frame.size.height = height;

if(frame.size.height > textView.frame.size.height){
    CGFloat diff = frame.size.height - textView.frame.size.height;
    textView.frame = CGRectMake(5, textView.frame.origin.y - diff, textView.frame.size.width, frame.size.height);
}
else if(frame.size.height < textView.frame.size.height){
    CGFloat diff = textView.frame.size.height - frame.size.height;
    textView.frame = CGRectMake(5, textView.frame.origin.y + diff, textView.frame.size.width, frame.size.height);
}
[textView setNeedsDisplay];
}