Masonary swift 2019-03-15

边距设置

 couponPriceLabel!.mas_makeConstraints({ (make) in
     make?.leading.greaterThanOrEqualTo()(self)?.setOffset(3)
     make?.centerX.equalTo()(self.mas_centerX)?.dividedBy()(2)//比例-除
     //等价 make?.centerX.equalTo()(self.mas_centerX)?.multipliedBy()(0.5)// 比例-乘
     make?.top.equalTo()(self)?.setOffset(18)
     make?.height.mas_equalTo()(27)
 })