SnapKit自动布局中断：“无法同时满足约束条件”

Question

Two view in UICollectionView Cell. UIImageView and UIView . Like this: layout

But when I make constraints, I get an error:

Unable to simultaneously satisfy constraints

    imgView.snp_makeConstraints { make in
        make.top.equalTo(contentView)//.inset(K.Space.Small)
        //make.bottom.equalTo(self.descView.snp_top)//.inset(K.Space.Small.negative())
        make.left.right.equalTo(contentView)
    }

    descView.snp_makeConstraints { make in
        make.bottom.equalTo(contentView)
        make.left.right.bottom.equalTo(contentView)
        make.height.equalTo(44)
        make.top.equalTo(imgView.snp_bottom)
    }

Error: error

Why?

edit: init collection view in vc viewDidLoad method. 【layout.itemSize 】 when first in ViewController error. but scroll down no error.

    let collectionContentInset = UIEdgeInsets(top: 0, left: 12, bottom: 0, right: 12)
    var collectionItemSize = DXLayoutSize(aspectRatio: 1.35)
    collectionItemSize.containerInset = collectionContentInset

    let layout = UICollectionViewFlowLayout()
    layout.itemSize = collectionItemSize.itemSize()
    layout.minimumInteritemSpacing = 6;
    layout.minimumLineSpacing = 0;

    collectionView = UICollectionView(frame: CGRectZero, collectionViewLayout: layout)
    collectionView!.backgroundColor = DXUIColor.Background.color()
    collectionView!.showsHorizontalScrollIndicator = false

    collectionView!.contentInset = collectionContentInset

Answer 1

Look at the error message. It says that you have a NSAutoResizingMaskLayoutConstraint which sets contentView 's height and width to 0. Just disable creating constraints from autoresizing masks:

contentView.translatesAutoresizingMaskIntoConstraints = false