[txt drawWithRect: options: attributes: context:]

+ (CGSize)textSizeForText:(NSString *)txt
{
    CGFloat width = [UIScreen mainScreen].applicationFrame.size.width * 0.75f;
    CGFloat height = MAX([JSBubbleView numberOfLinesForMessage:txt],
                         [txt numberOfLines]) * [JSMessageInputView textViewLineHeight];


    return [txt sizeWithFont:[JSBubbleView font]
           constrainedToSize:CGSizeMake(width - kJSAvatarSize, height + kJSAvatarSize)
               lineBreakMode:NSLineBreakByWordWrapping];

}

NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
  paragraphStyle.lineBreakMode = NSLineBreakByWordWrapping;

CGRect textRect = [text boundingRectWithSize:CGSizeMake(width - kJSAvatarSize, height + kJSAvatarSize)
                                      options:NSStringDrawingUsesLineFragmentOrigin
                                   attributes:@{NSParagraphStyleAttributeName: paragraphStyle.copy}
                                      context:nil];

  return textRect.size;

return ([text boundingRectWithSize:CGSizeMake(width - kJSAvatarSize, height + kJSAvatarSize)
                                      options:NSStringDrawingUsesLineFragmentOrigin
                                   attributes:@{NSParagraphStyleAttributeName: paragraphStyle.copy}
                                      context:nil]).size;