纯代码约束

方法一
import SnapKit

        colltionView!.snp.makeConstraints { (make) in
                    make.top.equalTo(0)
                    make.bottom.equalTo(0)
                    make.left.equalTo(0)
                    make.right.equalTo(0)
                }

https://www.jianshu.com/p/b61b93cde38a

方法二

        colltionView!.translatesAutoresizingMaskIntoConstraints = false

        let top:NSLayoutConstraint = NSLayoutConstraint(item: colltionView!, attribute: NSLayoutConstraint.Attribute.top , relatedBy:NSLayoutConstraint.Relation.equal, toItem:self.view, attribute:NSLayoutConstraint.Attribute.top, multiplier:1.0, constant: 0)
        colltionView!.superview!.addConstraint(top)

        let bottom:NSLayoutConstraint = NSLayoutConstraint(item: colltionView!, attribute: NSLayoutConstraint.Attribute.bottom , relatedBy:NSLayoutConstraint.Relation.equal, toItem:self.view, attribute:NSLayoutConstraint.Attribute.bottom, multiplier:1.0, constant: 0)
        colltionView!.superview!.addConstraint(bottom)

        let left:NSLayoutConstraint = NSLayoutConstraint(item: colltionView!, attribute: NSLayoutConstraint.Attribute.left , relatedBy:NSLayoutConstraint.Relation.equal, toItem:self.view, attribute:NSLayoutConstraint.Attribute.left, multiplier:1.0, constant: 0)
        colltionView!.superview!.addConstraint(left)

        let right:NSLayoutConstraint = NSLayoutConstraint(item: colltionView!, attribute: NSLayoutConstraint.Attribute.right , relatedBy:NSLayoutConstraint.Relation.equal, toItem:self.view, attribute:NSLayoutConstraint.Attribute.right, multiplier:1.0, constant: 0)
        colltionView!.superview!.addConstraint(right)