[]meshRender修改材质问题

    warehouse1 = Laya.Sprite3D.load("model/build/warehouse1/warehouse1.lh");



    scene.addChild(warehouse1);

    warehouse1.transform.rotate(new Laya.Vector3(0, 90, 0), false, false);

    warehouse1.transform.translate(new Laya.Vector3(0,0,0),false);

    

    warehouseMeshSprite3D1= warehouse1.getChildAt(0).getChildByName("Mesh1");

    var material  = warehouseMeshSprite3D1.meshRender.material;

    material.albedo = new Laya.Vector4(1,0,0,1);

换了一个模型就不行了，模型文件如下

 
会提示报错信息：

TypeError: Cannot read property 'meshRender' of null
at onCompleteWarehouse1 (file:///E:/LayaWorkspace/javaScriptLaya/src/warehouse.js:74:43)
at Handler.__proto.run (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:697:26)
at ResInfo.onLoaded (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:12723:28)
at EventHandler.__proto.runWith (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:713:27)
at ResInfo.__proto.event (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:483:28)
at LoaderManager.__proto._endLoad (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:12841:11)
at Loader.onLoaded (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:12818:10)
at EventHandler.__proto.runWith (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:713:27)
at Loader.__proto.event (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:483:28)
at Loader.__proto.endLoad (file:///E:/LayaWorkspace/javaScriptLaya/bin/libs/laya.core.js:12470:8) 
 
如果是只有一个lm文件的模型就没有问题，这种两个lm文件组成的就出问题了，试过其他同类型的模型，也都是同样的问题