ios - 说明 NSLayoutConstraint 到框架

Question

我想通过JSON字符串从服务器获取我的图层布局信息。并且布局信息与 的结构相同NSLayoutConstraint。

[
    {
        "secondItem": "1", // id of second item, can be use to find the related layer, the first item is a existed layer
        "firstAttribute": "left", // same as NSLayoutConstraint.Attribute
        "secondAttribute": "left",
        "relation": "equal",    // same as NSLayoutRelation
        "multiplier": "1",
        "constant": "10"
    },

    {
        "secondItem": "1",
        "firstAttribute": "right",
        "secondAttribute": "right",
        "relation": "equal",
        "multiplier": "1",
        "constant": "10"
    },

    {
        "secondItem": "1", 
        "firstAttribute": "top",
        "secondAttribute": "top",
        "relation": "equal",
        "multiplier": "1",
        "constant": "10"
    },

    {
        "secondItem": "1",
        "firstAttribute": "bottom",
        "secondAttribute": "bottom",
        "relation": "equal",
        "multiplier": "1",
        "constant": "10"
    }
]

这些JSON只是用来描述CALayer布局信息，不能直接应用于a UIView。

但是如何说明NSLayoutConstraintboundsCALayer和 position 属性呢？

谢谢！

标签： iosswiftautolayoutnslayoutconstraint