小编Luk*_*uke的帖子

我想将字符串的单个字符转换为整数,向其中添加2,然后将其转换回字符串.因此,A变为C,K变为M等.

我正在尝试定位标签,以便标签的顶部是UIViewController下方的2/3.所以我写了这个约束,但它给了我下面的错误.

NSLayoutConstraint *labelTopConstraint = [NSLayoutConstraint constraintWithItem:self.myLabel
                                         attribute:NSLayoutAttributeTop
                                         relatedBy:NSLayoutRelationGreaterThanOrEqual
                                            toItem:self.view
                                         attribute:NSLayoutAttributeHeight
                                        multiplier:0.66
                                          constant:0];

错误:

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', 
reason: '*** +[NSLayoutConstraint 
constraintWithItem:attribute:relatedBy:toItem:attribute:multiplier:constant:]: 
Invalid pairing of layout attributes'