Firebase - 用户身份验证，我的 userRef 不起作用答案

【问题标题】：Firebase - User authentication, my userRef won't workFirebase - 用户身份验证，我的 userRef 不起作用
【发布时间】：2016-05-05 18:40:10
【问题描述】：

我正在尝试向我的应用程序添加用户身份验证，但我不明白为什么我无法通过 FirebaseRecyclerAdapter 中的以下 ref 访问特定用户。

waypointsUrl = Constants.FIREBASE_URL + "/users/" + mUserId + "/";
            final Firebase userRef = new Firebase(waypointsUrl);

FATAL EXCEPTION: 
main Process: com.example.rasmusjosefsson.rjcar, PID: 7797
com.firebase.client.FirebaseException: Failed to bounce to type
at com.firebase.client.DataSnapshot.getValue(DataSnapshot.java:185)
at com.firebase.ui.FirebaseRecyclerAdapter.parseSnapshot(FirebaseRecyclerAdapter.java:161)
at com.firebase.ui.FirebaseRecyclerAdapter.getItem(FirebaseRecyclerAdapter.java:150)
at com.firebase.ui.FirebaseRecyclerAdapter.onBindViewHolder(FirebaseRecyclerAdapter.java:190)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:5471)
at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:5504)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4741)
at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4617)
at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:1994)
at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1390)
at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1353)
at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:574)
at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3028)
at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:2906)
at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3283)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.support.design.widget.HeaderScrollingViewBehavior.layoutChild(HeaderScrollingViewBehavior.java:122)
at android.support.design.widget.ViewOffsetBehavior.onLayoutChild(ViewOffsetBehavior.java:42)
at android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onLayoutChild(AppBarLayout.java:1170)
at android.support.design.widget.CoordinatorLayout.onLayout(CoordinatorLayout.java:814)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1743)
at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1586)
at android.widget.LinearLayout.onLayout(LinearLayout.java:1495)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.widget.FrameLayout.layoutChildren(FrameLayout.java:336)
at android.widget.FrameLayout.onLayout(FrameLayout.java:273)
at com.android.internal.policy.PhoneWindow$DecorView.onLayout(PhoneWindow.java:2678)
at android.view.View.layout(View.java:16630)
at android.view.ViewGroup.layout(ViewGroup.java:5437)
at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2171)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1931)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1107)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6013)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:858)
at android.view.Choreographer.doCallbacks(Choreographer.java:670)
at android.view.Choreographer.doFrame(Choreographer.java:606)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:844)
at android.os.Ha

我的 JSON 结构。还想知道是否可以使用“添加日期：2016-05-05 03:50:02”：作为关键？

{
  "users" : {
    "0057242b-81e2-4f97-bca7-b671212614ba" : {
      "email" : "kalle@hotmail.se",
      "waypoints" : {
        "Date added: 2016-05-05 03:50:02" : {
          "-KH-eHHxVpf--IcnYgIq" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-eK6z9vIefgcI5Pq2" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-eMIl8zB_Yq67SY69" : {
            "latitude" : 123,
            "longitude" : 123
          }
        }
      }
    },
    "1a96a633-7e67-41b8-9aa7-c70d4b7eb59c" : {
      "email" : "josefssons@hotmail.se",
      "waypoints" : {
        "Date added: 2016-05-05 03:46:21" : {
          "-KH-bcrZwOR2c3Ouc-hv" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-bhdzAatR84pcX1_h" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-dz0jw_UTsG2ojFJM" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-e0qLa2fY1fsFpiTS" : {
            "latitude" : 123,
            "longitude" : 123
          }
        },
        "Date added: 2016-05-05 03:51:09" : {
          "-KH-eXXo5OGSG7GIisMf" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-eZPi1spUbFUwkmfh" : {
            "latitude" : 123,
            "longitude" : 123
          },
          "-KH-eZSt613mKv1cJyox" : {
            "latitude" : 123,
            "longitude" : 123
          }
        },

我猜这里的某个地方是错误的，我没有看到。

@JsonIgnoreProperties(ignoreUnknown = true)
public class MyLatLngBack2 {

    @JsonProperty("email")
    private String email;

    @JsonProperty("waypoints")
    private TreeMap<String, Waypoints> waypoints;

    public MyLatLngBack2(String email, TreeMap<String, WaypointsBack2> waypoints) {
        this.email = email;
        this.waypoints = waypoints;
    }

    public MyLatLngBack2() {}

    public String getEmail() {
        return email;
    }

    public TreeMap<String, WaypointsBack2> getWaypoints() {
        return waypoints;
    }

    public void setWaypoints(TreeMap<String, WaypointsBack2> waypoints) {
        this.waypoints = waypoints;
    }
}

航点数据

@JsonIgnoreProperties(ignoreUnknown = true)
public class WaypointsBack2 {

    @JsonProperty("longitude")
    private double longitude;

    @JsonProperty("latitude")
    private double latitude;

    public WaypointsBack2(double latitude, double longitude) {
        this.latitude = latitude;
        this.longitude = longitude;
    }

    public WaypointsBack2() {
    }


    public double getLongitude() {
        return longitude;
    }

    public double getLatitude() {
        return latitude;
    }

}

下面是剩下的代码

 mRef = new Firebase(Constants.FIREBASE_URL);
            if (mRef.getAuth() == null) {
                loadLoginView();
            }


            try {
                mUserId = mRef.getAuth().getUid();
            } catch (Exception e) {
                loadLoginView();
            }


            mRecyclerView = (RecyclerView) findViewById(R.id.card_recycler_view);
            mRecyclerView.setHasFixedSize(false);
            LinearLayoutManager manager = new LinearLayoutManager(this);
            manager.setReverseLayout(false);
            mRecyclerView.setLayoutManager(manager);



            // https://todoapprj.firebaseio.com/users/1a96a633-7e67-41b8-9aa7-c70d4b7eb59c
            waypointsUrl = Constants.FIREBASE_URL + "/users/" + mUserId + "/";
            final Firebase userRef = new Firebase(waypointsUrl);



            //  (LatLngViewHolder.class, userRef) gives me bounce to blaha
            mRecycleViewAdapter = new FirebaseRecyclerAdapter<MyLatLngBack2, LatLngViewHolder>(MyLatLngBack2.class, R.layout.list_item, LatLngViewHolder.class, mRef) {
                @Override
                public void populateViewHolder(LatLngViewHolder latLngViewHolder, MyLatLngBack2 myLatLng, int position) {

                    // gets me the root email (wrong one)
                    String email =  myLatLng.getEmail();
                    }
            };

            mRecyclerView.setAdapter(mRecycleViewAdapter);
        }

【问题讨论】：

如果您在堆栈跟踪中向下滚动，将会有更准确的错误描述。那会很有帮助。
抱歉，刚刚更新。我不知道该怎么办，一直在尝试一切……但还不是正确的。
您将错误的引用传递给new FirebaseRecyclerAdapter<MyLatLngBack2, LatLngViewHolder>(MyLatLngBack2.class, R.layout.list_item, LatLngViewHolder.class, mRef)。最后一个参数应该是userRef。
我想我不清楚当我传入 userRef 时，我得到了 Bounce 堆栈跟踪，如果我通过 mRef，我至少可以到达用户 root。但不会因为反弹而进一步。
当我从MyLatLangBack2 POJO 中删除waypoints 时：public MyLatLngBack2(String email, HashMap<String, WaypointsBack2> waypoints) { this.email = email; this.waypoints = waypoints; } 然后它将停止失败反弹异常，那么我应该如何真正构建我的 POJO？

标签： android firebase firebase-realtime-database firebase-authentication

【解决方案1】：

我找到了弹跳失败的解决方案，我确实将 MyLatLng POJO 更改为以下：

@JsonIgnoreProperties(ignoreUnknown = true)
public class LatLngsModel {
    public Map<String, Map <String, MyWaypoint>>  latLngs;

    public LatLngsModel() {
    }

    public LatLngsModel(Map<String, Map <String, MyWaypoint>>  myLatLngs) {
        this.latLngs = myLatLngs;
    }

    public Map<String, Map <String, MyWaypoint>> getMyWaypoints() {
        return latLngs;
    }
}

【讨论】：