ios7 uitextview计算Unicode上的高度模糊行为

Question

我在TableView Cell中使用UITextView。为此，我必须计算UITextview的高度。

经过大量的磨头后，我找到了一种合理可靠的方法来计算UITextView的高度。我复制了与Cell相同的虚拟UITxtView并分配了文本。在设置框架后，我从textView.frame.size.height获取高度。

但是只有在为textView分配长的unicode文本时才会出现问题。

这是func

-(float)calculateHeight:(NSString*)msg nick:(NSString*)nick
{

textView = [[UITextView alloc] init];
PrivateChatCellRight * pc = [[PrivateChatCellRight alloc] init];
NSArray *topLevelObjects = [[NSBundle mainBundle] loadNibNamed:@"PrivateChatCellRight" owner:nil options:nil];
for(id currentObject in topLevelObjects)
{
    if([currentObject isKindOfClass:[PrivateChatCellRight class]])
    {
        pc = (PrivateChatCellRight *)currentObject;
        break;
    }
}

textView = pc.lblMessage;
{
    textView.text = msg;
    if ([textView respondsToSelector:@selector(setAttributedText:)])
    {

        UIFont *boldFont = MyriadProBoldWithSize13Pt;
        UIFont *regularFont = btMyriadProRegularWithSize14Pt; //font from define


        // Creating simmilar attributes
        NSDictionary *attrs = [NSDictionary dictionaryWithObjectsAndKeys:
                               regularFont, NSFontAttributeName,
                               nil];
        NSDictionary *subAttrs = [NSDictionary dictionaryWithObjectsAndKeys:
                                  boldFont, NSFontAttributeName, nil];
        const NSRange range = NSMakeRange(0,2); // range of " 2012/10/14 ". Ideally this should not be hardcoded

        // Create the attributed string (text + attributes)
        NSMutableAttributedString *attributedText =
        [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"%@: %@", nick ,msg]
                                               attributes:attrs];
        [attributedText setAttributes:subAttrs range:range];

        // Set it in our UILabel and we are done!
        [textView setAttributedText:attributedText];
    }
    else
    {
    }
    textView.textColor = textSettingsColor;
    [textView sizeToFit];
    NSLog(@"height %f", textView.frame.size.height);
    textView.frame = CGRectMake(textView.frame.origin.x, textView.frame.origin.y, textView.frame.size.width + 5, textView.frame.size.height + 5);


    return textView.frame.size.height;
}
}