android - 如何在 flutter 中访问 DocumentReference 数组？

Question

我想访问当前登录用户的所有 reg_events。我现在有以下代码

       stream: Firestore.instance.collection('users').document(email).snapshots(),
       builder: (context, snapshot){
         if(!snapshot.hasData){
           return Text("Loading..");
         }
         return Center(
          child: new Container(
            child: new PageView.builder(
                onPageChanged: (value) {
                  setState(() {
                    currentpage = value;
                  });
                },
                controller: controller,
                itemCount: snapshot.data['reg_events'].length,
                itemBuilder: (context, index) => builder(index, snapshot.data)),
          ),
        );
       }
     ),

“ build 者”是:

builder(int index, DocumentSnapshot document) {
    return new AnimatedBuilder(
      animation: controller,
      builder: (context, child) {
        double value = 1.0;
        if (controller.position.haveDimensions) {
          value = controller.page - index;
          value = (1 - (value.abs() * .5)).clamp(0.0, 1.0);
        }

        return new Center(
          child: new SizedBox(
            height: Curves.easeOut.transform(value) * 200,
            width: Curves.easeOut.transform(value) * 1000,
            child: child,
          ),
        );
      },
      child: new Card(
        child: Text(document.data['reg_events'][0].toString(),
        textAlign: TextAlign.center,
        style: TextStyle(fontSize: 15, color: Colors.white),),
        margin: const EdgeInsets.all(10.0),
        color: index % 2 == 0 ? Colors.blue : Colors.red,
      ),
    );
  }

但它输出“'DocumentReference'的实例”。如何访问此文档引用？

Answer 1

也许它不能将 reg_event 理解为列表，所以试试这个，

 stream: Firestore.instance.collection('users').document(email).snapshots(),
  builder: (context, snapshot){
     List regEvent = new List();
     if(snapshot.hasData){
        regEvent = snapshot.data['reg_events'];
      }
      if(!snapshot.hasData){
        return Text("Loading..");
      }
      return Center(
           child: new Container(
                 child: new PageView.builder(
                         onPageChanged: (value) {
                                setState(() {
                                      currentpage = value;
                                });
                          },
                         controller: controller,
                         itemCount: regEvent.length,
                         itemBuilder: (context, index) { 
                               print(regEvent[index]);
                               return builder(index, snapshot.data)),}
                      ),
               );
         }
),