如何从新的iOS 7方法sizeWithAttributes返回多行文本CGSize？
我希望这能产生与sizeWithFont:constrainedToSize相同的结果.
NSString *text = @"Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus eu urna quis lacus imperdiet scelerisque a nec neque. Mauris eget feugiat augue, vitae porttitor mi. Curabitur vitae sollicitudin augue. Donec id sapien eros. Proin consequat tellus in vehicula sagittis. Morbi sed felis a nibh hendrerit hendrerit. Lorem ipsum dolor sit."
CGSize textSize = [text sizeWithAttributes:@{ NSFontAttributeName : [UIFont fontWithName:@"HelveticaNeue-Light" size:16.0] }];
此方法仅生成单行文本的高度.