If I use virtualLayout on Tree componenet layout with custom LayoutGroupTreeItemRenderer, when open some branch to show leafs, scroll down and back can't click (random) some of branches. And the GPU memory is also not decreased when close a branch.

The Itemrenderer (BackgroundTreeItemRenderer):

<?xml version="1.0"?>
<base:BaseTreeItemRenderer xmlns:fx="http://ns.adobe.com/mxml/2009"
                           xmlns:feathersui="http://gotocore/feathersui"
                           xmlns:mxml="library://ns.feathersui.com/mxml" xmlns:text="starling.text.*"
                           addedToStage="addedToStageHandler(event)"
                           removedFromStage="removedFromStageHandler(event)"
                           implements="feathers.dragDrop.IDragSource" xmlns:base="view.renderer.base.*"
>
    <base:states>
        <mxml:State name="branch"/>
        <mxml:State name="leaf"/>
    </base:states>
    <base:layout>
        <mxml:VerticalLayout paddingLeft="{this.indent}" padding="10"/>
    </base:layout>
    <fx:Script><![CDATA[
        import controller.AssetController;

        import core.notification.CoreNotification;

        import feathers.controls.ImageLoader;
        import feathers.dragDrop.DragData;
        import feathers.dragDrop.DragDropManager;

        import feathers.events.DragDropEvent;

        import feathers.utils.touch.TapToTrigger;

        import model.DragFormat;
        import model.base.interfaces.IBackgroundModel;


        import starling.display.Quad;

        import starling.events.Event;
        import starling.events.Touch;
        import starling.events.TouchPhase;
        import starling.utils.ScaleMode;

        [Bindable]
        private var indent:Number;

        [Bindable]
        private var backgroundModel:IBackgroundModel;

        private function addedToStageHandler(event:Event):void {
            new TapToTrigger(this);

            this.addEventListener(starling.events.TouchEvent.TOUCH, touchHandler);
            this.addEventListener(DragDropEvent.DRAG_START, dragStartHandler);
            this.addEventListener(DragDropEvent.DRAG_COMPLETE, dragComplete);
        }

        private var _touchID:int = -1;

        private var avatar:ImageLoader;

        private function dragComplete(event:DragDropEvent):void {
            if (this.avatar)
                this.avatar.dispose();
        }

        private function touchHandler(event:starling.events.TouchEvent):void {
            if (!this.backgroundModel) return;
            if (DragDropManager.isDragging)
                return;

            if (this._touchID >= 0) {

                var touch:Touch = event.getTouch(this, null, this._touchID);
                if (touch.phase == TouchPhase.MOVED) {
                    if (Math.abs(touch.getMovement(this).y) > 10 || this.owner.isScrolling)
                        return;
                    this._touchID = -1;


                    var dragData:DragData = new DragData();
                    dragData.setDataForFormat(DragFormat.BACKGROUND, this.backgroundModel.clone);
                    this.avatar = new ImageLoader();
                    this.avatar.width = this.imageLoader.width;
                    this.avatar.height = this.imageLoader.height;
                    this.avatar.scaleMode = ScaleMode.NO_BORDER;
                    this.avatar.source = this.imageLoader.source;
                    this.avatar.alignPivot();

                    this.avatar.addEventListener(starling.events.Event.COMPLETE, function (event:Event):void {
                        avatar.alignPivot();
                    });

                    DragDropManager.startDrag(this, touch, dragData, this.avatar);
                    CoreNotification.createNotification(DragFormat.PROP + ".start.drag").send();
                }
                else if (touch.phase == TouchPhase.ENDED) {
                    this._touchID = -1;
                }
            }
            else {
                touch = event.getTouch(this, TouchPhase.BEGAN);
                if (!touch) {
                    return;
                }
                this._touchID = touch.id;
            }
        }

        private function dragStartHandler(event:DragDropEvent):void {
            this.owner.stopScrolling();
        }

        function onTriggered(event:starling.events.Event):void {
            this.owner.toggleBranch(this._data, !this._isOpen);
        }

        override public function set isBranch(value:Boolean):void {
            super.isBranch = value;
            this.currentState = this.isBranch ? "branch" : "leaf";

            if (this.isBranch) {
                if (!this.hasEventListener(starling.events.Event.TRIGGERED)) {
                    this.addEventListener(starling.events.Event.TRIGGERED, this.onTriggered);
                }

            } else {
                if (this.hasEventListener(starling.events.Event.TRIGGERED)) {
                    this.removeEventListener(starling.events.Event.TRIGGERED, this.onTriggered);
                }

            }
        }

        override public function set location(value:Vector.<int>):void {
            super.location = location;
            if (!value)
                return;

            this.indent = 30 * value.length - 1;
        }

        override public function set data(value:Object):void {
            super.data = value;
            if (!data)
                return;
            if (!data.backgroundModel)
                return;

            this.backgroundModel = this.data.backgroundModel as IBackgroundModel;

        }

        private function removedFromStageHandler(event:Event):void {
            log(this +" removed from stage");

            this.backgroundModel = null;
            this.imageLoader.source = null;
            this.imageLoader.dispose();
            this.dispose();
        }
        ]]></fx:Script>
    <feathersui:GuiLayoutGroup includeIn="branch" width="150" height="84" clipContent="true"
                               backgroundSkin="{new Quad(1,1,0xaaaaaa)}">
        <feathersui:layout>
            <mxml:AnchorLayout/>
        </feathersui:layout>
        <feathersui:GuiImageLoader scaleMode="none" verticalAlign="middle" horizontalAlign="center"
                                   source="{AssetController.getInstance().getTexture('icon/folder')}">
            <feathersui:layoutData>
                <mxml:AnchorLayoutData bottom="0" top="0" left="0" right="0"/>
            </feathersui:layoutData>
        </feathersui:GuiImageLoader>
        <feathersui:GuiLabel text="{data.text}" backgroundSkin="{alphaWhite}">
            <feathersui:fontStyles>
                <text:TextFormat horizontalAlign="center"/>
            </feathersui:fontStyles>
            <feathersui:layoutData>
                <mxml:AnchorLayoutData bottom="0" left="0" right="0" percentWidth="100"/>
            </feathersui:layoutData>
        </feathersui:GuiLabel>
    </feathersui:GuiLayoutGroup>
    <feathersui:GuiLayoutGroup includeIn="leaf" width="150" height="84" clipContent="true">
        <feathersui:layout>
            <mxml:AnchorLayout/>
        </feathersui:layout>
        <feathersui:GuiImageLoader id="imageLoader" source="{backgroundModel.thumbnail}" textureCache="{null}"
                                   scaleMode="noBorder">
            <feathersui:layoutData>
                <mxml:AnchorLayoutData percentHeight="100" percentWidth="100"/>
            </feathersui:layoutData>

        </feathersui:GuiImageLoader>

        <feathersui:GuiLabel text="{this.backgroundModel.resource.name}" backgroundSkin="{alphaWhite}">
            <feathersui:fontStyles>
                <text:TextFormat horizontalAlign="center"/>
            </feathersui:fontStyles>

            <feathersui:layoutData>
                <mxml:AnchorLayoutData bottom="0" left="0" right="0" percentWidth="100"/>
            </feathersui:layoutData>
        </feathersui:GuiLabel>
    </feathersui:GuiLayoutGroup>
</base:BaseTreeItemRenderer>

The Tree implementation:

<feathersui:GuiTree id="tree" dataProvider="{Resources.getInstance().backgroundTreeProvider}"
                            backgroundSkin="{new Quad(1,1,0xCCCCCC)}"
                            itemRendererType="view.renderer.BackgroundTreeItemRenderer" hasElasticEdges="false">
            <feathersui:layout>
                <layout:VerticalLayout useVirtualLayout="true" />
            </feathersui:layout>
            <feathersui:layoutData>
                <layout:VerticalLayoutData percentHeight="100" percentWidth="100"/>
            </feathersui:layoutData>
        </feathersui:GuiTree>