从 MovieClip 中删除内容（图形线）

Question

我有一个图像库，它加载详细图像，然后根据图像尺寸在图像旁边画一条线。单击图像将返回到主图像缩略图列表，然后单击缩略图将另一图像加载到细节容器中。一切工作正常，除了线条在细节图像卸载时不会消失，而是累积。有没有办法清除 lineDrawing MovieClip 的内容而不将其从舞台上删除，以便我可以在其中绘制新线？我尝试过在 MovieClip 上删除Child，但随后线条完全消失，与将 lineDrawing.clear() 放在 setupDetail 函数的顶部相同。到目前为止，这是我的（相关）代码，任何帮助将不胜感激，我被难住了！

var detailImage:Loader = new Loader();
var lineDrawing:MovieClip = new MovieClip();

setupDetail();

function setupDetail():void {
    detail.visible = false;
    detail.buttonMode = true;
    detail.closeMessage.mouseEnabled = false;

    detail.addChild(detailImage);

    detailImage.contentLoaderInfo.addEventListener(Event.COMPLETE, fullyLoaded);

    // make sure detail is above the gallery
    addChild(detail);

    detail.addEventListener(MouseEvent.CLICK, onCloseDetail, false, 0, true);
}

function fullyLoaded(evt:Event):void {

    var imgHeight:int = evt.target.content.height;
    var imgWidth:int = evt.target.content.width;

    var hOffset:int = imgWidth + 5 + 27;
    var vOffset:int = imgHeight + 5;

    detail.addChild(lineDrawing);

    if(imgWidth == 600) {
        lineDrawing.graphics.lineStyle(3,0x9a9345);
        lineDrawing.graphics.moveTo(28,vOffset);
        lineDrawing.graphics.lineTo(626,vOffset);
    }
    else if(imgHeight == 600) {
        lineDrawing.graphics.lineStyle(3,0x9a9345);
        lineDrawing.graphics.moveTo(hOffset, 1);
        lineDrawing.graphics.lineTo(hOffset, 599);
    }
}

function onCloseDetail(evt:MouseEvent):void {

    // only allow it to be closed if it is at least 90% opaque
    if (detailImage.alpha>.9){
      detailImage.unload();
      TweenLite.to(detail,.5, {autoAlpha:0});
      detailImage.unload();
      detail.visible = false;
    }
}

Answer 1

lineDrawing.graphics.clear()