使用 iOS 7 SDK 构建时 UITextView 会自动换行

我有一个UITextView里面一个UIScrollView效果很好iOS 6建造自xcode 4.x，但是现在构建xcode 5它无法正常工作，即使在iOS 6.

问题是文本会随着屏幕宽度换行，即使UITextView and UIScrollView具有较大的宽度。我使用这段代码来计算出新的宽度和高度UITextView，即使文本视图向左/向右滚动，文本也会被换行，就好像宽度只是屏幕的宽度一样。

Thanks

self.responceTextView.text = [NSString stringWithFormat:@"%@%@",_responceTextView.text,responce];
[self textViewDidChange:self.responceTextView];

- (void)textViewDidChange:(UITextView *)textView
{
    // Recalculate size of text field
    CGSize maxSize = CGSizeMake(MAXFLOAT, MAXFLOAT);
    CGSize reqSize = [textView.text sizeWithFont:[UIFont fontWithName:@"Courier" size:12] constrainedToSize:maxSize lineBreakMode:NSLineBreakByClipping];

    self.responceTextView.frame = CGRectMake(0, 0, reqSize.width+16, reqSize.height+16);

    // Resize scroll view if needs to be smaller so text stays at top of screen
    CGFloat maxScrollHeight = maxScrollViewSize.size.height;
    if (self.responceTextView.frame.size.height < maxScrollHeight) {
        self.responceScrollView.frame = CGRectMake(self.responceScrollView.frame.origin.x, self.responceScrollView.frame.origin.y, self.responceScrollView.frame.size.width, self.responceTextView.frame.size.height);
    } else {
        self.responceScrollView.frame = maxScrollViewSize;
    }

    // Set content size
    self.responceScrollView.contentSize = CGSizeMake(self.responceTextView.frame.size.width, self.responceTextView.frame.size.height);

    [self scrollToCursor];
}

编辑 - -

好吧，看来是这样sizeWithFont在 iOS 7 中已弃用。奇怪的是我没有收到编译器警告。 它在 iOS 6 上不起作用仍然没有意义（或者当使用 iOS 7 SDK 构建时它被完全删除？）

我已经尝试过这两种替代方案，但得到的尺寸完全相同。

NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:
                                [UIFont fontWithName:@"Courier" size:12], NSFontAttributeName,
                                nil];
CGRect rect = [textView.text boundingRectWithSize:maxSize options:NSLineBreakByClipping | NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading attributes:attributes context:nil];

返回：{{0, 0}, {439.27148, 168}}

CGSize rect2 = [textView.text sizeWithAttributes:attributes];

返回：{439.27148, 168}

上面的原始返回{439.27148, 168}

他们都应该回归更广阔的视野。

编辑2---- 从上面看来，返回的帧是正确的（439 宽），但是文本仍然被文字包装在文本视图内。

尝试使用：

[textView.text boundingRectWithSize:CGSizeMake(txtFrame.size.width, CGFLOAT_MAX)
                           options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading
                           attributes:[NSDictionary dictionaryWithObjectsAndKeys:textView.font,NSFontAttributeName, nil] context:nil];

字符串测量似乎很麻烦。对于我所做的测试来说，这是唯一提供正确尺寸的选项组合。

我在 iOS7 中成功使用了以下代码（它是UITextField具有最小和最大高度。当文本的高度变大时MAX_HEIGHT_MESSAGE_TEXTBOX，滚动条出现在UITextField).

const float MAX_HEIGHT_MESSAGE_TEXTBOX = 80;
const float MIN_HEIGHT_MESSAGE_TEXTBOX = 30;


- (void)setFrameToTextSize:(CGRect)txtFrame textView:(UITextView *)textView
{

    if(txtFrame.size.height > MAX_HEIGHT_MESSAGE_TEXTBOX)
    {
        //OK, the new frame is to large. Let's use scroll
        txtFrame.size.height = MAX_HEIGHT_MESSAGE_TEXTBOX;
        textView.scrollEnabled = YES;
        [textView scrollRangeToVisible:NSMakeRange([textView.text length], 0)];
    }
    else
    {
        if (textView.frame.size.height < MIN_HEIGHT_MESSAGE_TEXTBOX) {
             //OK, the new frame is to small. Let's set minimum size
            txtFrame.size.height = MIN_HEIGHT_MESSAGE_TEXTBOX;
        }
        //no need for scroll
        textView.scrollEnabled = NO;
    }
    //set the frame
    textView.frame = txtFrame;
}

- (void)setframeToTextSize:(UITextView *)textView animated:(BOOL)animated
{
    //get current height
    CGRect txtFrame = textView.frame;

    //calculate height needed with selected font. Note the options.
    //append a new line to make space for the cursor after user hit the return key
    txtFrame.size.height =[[NSString stringWithFormat:@"%@\n ",textView.text]
                           boundingRectWithSize:CGSizeMake(txtFrame.size.width, CGFLOAT_MAX)
                           options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading
                           attributes:[NSDictionary dictionaryWithObjectsAndKeys:textView.font,NSFontAttributeName, nil] context:nil].size.height;

    if (animated) {
        //set the new frame, animated for a more nice transition
        [UIView animateWithDuration:0.2 delay:0.0 options:UIViewAnimationOptionCurveEaseOut |UIViewAnimationOptionAllowAnimatedContent animations:^{
            [self setFrameToTextSize:txtFrame textView:textView];
        } completion:nil];
    }
    else
    {
        [self setFrameToTextSize:txtFrame textView:textView];
    }
}

- (void)textViewDidChange:(UITextView *)textView
{
    [self setframeToTextSize:textView animated:YES];
}

EDIT

当弦测量正确时，您可能需要更改lineBreakModeon the UITextView的文本容器。 (NSTextContainer是 iOS7 中的一个新类，包含有关如何布局文本的信息）：

textView.textContainer.lineBreakMode = NSLineBreakByCharWrapping; // default is NSLineBreakByWordWrapping 

祝你好运！