使用sizeThatFits的正确方法是:尺寸是否与UILabel匹配?

At the moment I have a label being sized correctly using [aString sizeWithFont:constrainedToSize:lineBreakMode:] but I've introduced rotation into my device and with a flexible width and height this results in my UILabel stretching width ways (because its set relative to the main view) but not then contracting height-wise to compensate for the extra space.At the moment I have a label being sized correc