layer.removeChild(layer)

Remove a layer from the children of this layer. (Alias: removeSubLayer)
译：从这层移除子层。（别名：removesublayer）

Arguments（参数）

layer — A layer object. 译：一层对象

layerA = new Layer
layerB = new Layer
    parent: layerA

layerA.removeChild(layerB)

print layerB.parent
# Output: null