ActionScript 3 Working With Display Objects
Syntax
addChild(child)- adds a new item to this object's child tree as the topmost element.addChildAt(child, index)- adds a new item to this object's child tree at a specified position. The bottom-most item has index of 0.getChildAt(index)- returns a child with given index.getChildIndex(child)returns the index of a direct child of this object. Otherwise an exception is thrown.removeChild(child)- removes the specified direct child from this object's child tree. Throws exception if the supplied child's parent is not equal tothis.removeChildAt(index)- removes a child selected by index instead of reference. Throws exception if the child tree is not this wide.removeChildren(beginIndex:int = 0, endIndex:int = 0x7fffffff))- added in Flash Player 11, removes a subset of children by index range, or all children if called with no parameters.setChildIndex(child,index)- changes the child's index to the new value, shifting all children in between to occupy the released spot.swapChildren(child1,child2)- swaps the two children's positions in display list, not affecting positions of other children.swapChildrenAt(index1,index2)- swaps children located by their indexes.
Remarks
The display list is actually a tree, and is visualized with depth first algorithm. Any object listed earlier will be displayed earlier, and might be obscured by objects listed later. All techniques that can be used against a tree can be applied to working with display list.
