javascript - Polymer v1.0 - 数据绑定(bind)更改未传播

Question

尝试使用 Polymer v1.0，目前正在加载 2 个数据集。第一组将设置 View 并重复我的自定义元素。第二组是异步加载的，加载后它将尝试通过路由 ID 进行匹配(如果可用)。匹配时，它将自身作为对象插入到第一个对象中。

当我这样做时， View 不会更新，但如果我执行 console.log 并跟踪它，数据就在那里。

我发现如果我要清除第一个对象，使用异步并稍后将其设置回来， View 会更新，但这会导致我的显示暂时空白。我怎样才能强制它用更新的内容重新绘制？

第一个设置项目的 View 。

[ 
        {
            "anchors":[ 
                {"anchorid":1, 
                 "routes":[ 
                     {"name":"route 1", "routeid":1 },
                     {"name":"route 2", "routeid":2 },
                     {"name":"route 3", "routeid":3 }  
                 ] 
                },
                {"anchorid":2, 
                 "routes":[ 
                     {"name":"route 4", "routeid":4 },
                     {"name":"route 5", "routeid":5 },
                     {"name":"route 6", "routeid":6 }  
                 ] 
                }
            ]
        },
        {
            "anchors":[ 
                {"anchorid":3, 
                 "routes":[ 
                     {"name":"route 7", "routeid":7 },
                     {"name":"route 8", "routeid":8 },
                     {"name":"route 9", "routeid":9 }  
                 ] 
                },
                {"anchorid":4, 
                 "routes":[ 
                     {"name":"route 10", "routeid":10 },
                     {"name":"route 11", "routeid":11 },
                     {"name":"route 12", "routeid":12 }  
                 ] 
                }
            ]
        }
    ]

第二个数据集

 [
  {"routeid":3, "status":2},
  {"routeid":5, "status":3},
  {"routeid":1, "status":1}
 ]

我的元素代码

    <dom-module id="anchor-listdebug">
    <template>
        <h1>Anchor list</h1>
        <template is="dom-repeat" items="{{data}}">
            <h2>Anchor Group </h2>
            <template is="dom-repeat" items="{{item.anchors}}" as="anchordata">
                <anchor-item anchor="{{anchordata}}"></anchor-item>

            </template>
        </template>
    </template>

    <script>
        Polymer ({
            is:"anchor-listdebug",
            ready : function () {
                //data is loaded here via iron-ajax
                this.data = data;
                //data2 is loaded on data response
                this.data2 = data2;

                // emulate 2nd set of data loading, if this.processData is called immediately, content updates fine.
                this.async (this.processData, 1000);
            },
            processData: function () {
                this.data.forEach (function (element) {
                    element.anchors.forEach (function (anchorElement){
                        anchorElement.routes.forEach (function (routeElement){
                            var myID = routeElement.routeid;
                            var data = this.data2.filter(function (record){
                                return record.routeid == myID;
                            });
                            if (data.length >0) {
                                data = data[0];
                                routeElement.data = data;
                            }
                        }); 
                    });
                });
            }
        });
    </script>
</dom-module>

<dom-module id="anchor-item">
    <template>
        <h2>Anchor ID: {{anchor.anchorid}} </h2>
        <template is="dom-repeat" items="{{anchor.routes}}" as="routedata">

            <route-item route="{{routedata}}"></route-item>
        </template>

    </template>

    <script>
        Polymer ({
            is:"anchor-item",
            properties: {
                anchor:{ type:Object, notify:true}
            }

        });
    </script>
</dom-module>

<dom-module id="route-item">
    <template>
        <h3>Route id: <span>{{route.routeid}}</span></h3>
        <h3>Route name: <span>{{route.name}}</span></h3>
        <h3>Route status: <span>{{route.data.status}}</span></h3>

    </template>

    <script>
        Polymer ({
            is:"route-item",
            properties: {
                route:{ type:Object, notify:true}
            }

        });
    </script>
</dom-module>

Answer 1

确保使用 set API 来操作对象 ( docs )。而不是this.data.anchors = someValue使用this.set("data.anchors", someValue) 。