Question

我想获得特定用户的所有任务（约束数为1），但只有可用的用户（约束数为2）。

我知道我可以通过＆＃39;顺序克服一个约束。并且＆＃39;等于＆＃39;功能，但我没有克服第二个问题。

这是我的firebase db：

这是我在应用程序中的当前结果（完成任务就在那里！我不想要它！）：

这是我的相关代码：

    public class PendingFragmentUser extends Fragment {

    private String TAG = "dDEBUG";
    private RecyclerView mPendingList;

    private DatabaseReference mMissionsDb;
    private FirebaseAuth mAuth;

    private String mCurrent_user_id;

    private View mMainView;

    Query queries;

    public PendingFragmentUser() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {


        mMainView = inflater.inflate(R.layout.fragment_pending_user, container, false);

        mPendingList = (RecyclerView)mMainView.findViewById(R.id.pending_recycler_user);
        mAuth = FirebaseAuth.getInstance();

        mCurrent_user_id = mAuth.getCurrentUser().getUid();

        mMissionsDb = FirebaseDatabase.getInstance().getReference().child("Missions");
        queries = mMissionsDb.orderByChild("user_uid").equalTo(mCurrent_user_id);
        mMissionsDb.keepSynced(true);

        mPendingList.setHasFixedSize(true);
        mPendingList.setLayoutManager(new LinearLayoutManager(getContext()));

        // Inflate the layout for this fragment
        return mMainView;
    }

    @Override
    public void onStart() {
        super.onStart();

        final FirebaseRecyclerAdapter<Mission, PendingFragmentUser.MissionsViewHolder> firebaseMissionsUserRecyclerAdapter = new FirebaseRecyclerAdapter<Mission, PendingFragmentUser.MissionsViewHolder>(
                Mission.class,
                R.layout.missions_single_layout,
                PendingFragmentUser.MissionsViewHolder.class,
                queries
        ) {
            @Override
            protected void populateViewHolder(PendingFragmentUser.MissionsViewHolder missionViewHolder, final Mission missionModel, final int missionPosition) {
//                Log.d(TAG, "inside populateViewHolder" + missionModel.getType() + " , " + missionModel.getDescription());
                missionViewHolder.setMissionName(missionModel.getType());
                missionViewHolder.setMissionDescription(missionModel.getDescription());
                missionViewHolder.setMissionStatus(missionModel.getStatus());

            }
        };

        mPendingList.setAdapter(firebaseMissionsUserRecyclerAdapter);
    }

    public static class MissionsViewHolder extends RecyclerView.ViewHolder {
        View mView;
        Button button ;

        public MissionsViewHolder(View itemView) {
            super(itemView);
            mView = itemView;
            button = (Button)mView.findViewById(R.id.pending_single_button);

        }

        public void setMissionName(String name){
            TextView mMissionNameView = mView.findViewById(R.id.mission_single_name);
            mMissionNameView.setText(name);
        }

        public void setMissionStatus(String status){
            TextView mMissionStatusView = mView.findViewById(R.id.mission_single_status);
            mMissionStatusView.setText(status);
            if (status.equals("Available")){
                mMissionStatusView.setTextColor(Color.parseColor("#008000"));;
            } else {
                mMissionStatusView.setTextColor(Color.parseColor("#FF0000"));;
            }
        }

        public void setMissionDescription(String description){
            TextView mMissionDescriptionView = mView.findViewById(R.id.mission_single_description);
            mMissionDescriptionView.setText(description);

        }
    }
}

如何克服这种火力基础限制？

过滤特定用户的所有任务：

    queries = mMissionsDb.orderByChild("user_uid").equalTo(mCurrent_user_id);

现在我想做：

    queries = mMissionsDb.orderByChild("user_uid").equalTo(mCurrent_user_id).orderByChild("status").equalTo("Available");

但它在firebase中是不可能的。

此外，我必须使用实时适配器，因为它的关键是我的UI准确显示数据库中DB的更改延迟最小。感谢

如何在firebase android链接查询？

0 个答案: