FairyGUI.GComponent._SetChildIndex C# (CSharp) Method

        int _SetChildIndex(GObject child, int oldIndex, int index)
        {
            int cnt = _children.Count;
            if (index > cnt)
                index = cnt;

            if (oldIndex == index)
                return oldIndex;

            _children.RemoveAt(oldIndex);
            if (index >= cnt)
                _children.Add(child);
            else
                _children.Insert(index, child);

            if (child.inContainer)
            {
                int displayIndex = 0;
                if (_childrenRenderOrder == ChildrenRenderOrder.Ascent)
                {
                    for (int i = 0; i < index; i++)
                    {
                        GObject g = _children[i];
                        if (g.inContainer)
                            displayIndex++;
                    }
                    container.SetChildIndex(child.displayObject, displayIndex);
                }
                else if (_childrenRenderOrder == ChildrenRenderOrder.Descent)
                {
                    for (int i = cnt - 1; i > index; i--)
                    {
                        GObject g = _children[i];
                        if (g.inContainer)
                            displayIndex++;
                    }
                    container.SetChildIndex(child.displayObject, displayIndex);
                }
                else
                {
                    UpdateContext.OnBegin -= _buildDelegate;
                    UpdateContext.OnBegin += _buildDelegate;
                }

                SetBoundsChangedFlag();
            }

            return index;
        }