Masonry Label的宽度自适应

当 label想要宽度自适应时 加上下面的话
“Content Compression Resistance”和“Content Hugging”

1.宽度不够时

[_label1 setContentCompressionResistancePriority:UILayoutPriorityRequired                                         forAxis:UILayoutConstraintAxisHorizontal];

2.宽度够时

[label setContentHuggingPriority:UILayoutPriorityRequired forAxis:UILayoutConstraintAxisHorizontal];