Question

我正在尝试从Firebase数据库获取没有setValue的整个节点。我在Google上获得了各种代码，但没有任何效果。这是我的JSON：

myAppInfo.json

    {
      "AppInfo" : {

          "AppName" : "MyDemo1",
          "VersionName" : "1.0",
          "VersionCode" : "1.1"
        }
    }

Firebase方法

public void AppversionCheck() {

    Log.v(Constants.TAG, "AppversionCheck ");

    //String UserId = ref.child("AppInfo").push().getKey();
    ref = new Firebase(Config.FIREBASE_URL);

    //AppInfo appInfo = new AppInfo();
    //appInfo.setAppName("AppInfo");
    //ref.child("AppInfo").child("AppName").setValue("App1");
    ref.child("AppInfo")./*child(UserId).*/child("AppName").setValue("App1");
    //mDatabase = FirebaseDatabase.getInstance().getReference("AppInfo");
    ref.child("AppInfo")/*.child(UserId)*/.addChildEventListener(new ChildEventListener() {


        @Override
        public void onChildAdded(DataSnapshot dataSnapshot, String s) {


            Log.v(Constants.TAG, "FireBaseCalled 11");
            //Getting the data from snapshot
            //AppInfo appInfo = postSnapshot.getValue(AppInfo.class);
            Log.v(Constants.TAG, "postSnapshot " + dataSnapshot.getChildren());
        }

        @Override
        public void onChildChanged(DataSnapshot dataSnapshot, String s) {


            Log.v(Constants.TAG, "FireBaseCalled 22");
            //Getting the data from snapshot
            //AppInfo appInfo = postSnapshot.getValue(AppInfo.class);
            Log.v(Constants.TAG, "postSnapshot " + dataSnapshot.getChildren());

        }

        @Override
        public void onChildRemoved(DataSnapshot dataSnapshot) {


            Log.v(Constants.TAG, "FireBaseCalled1 33");
            //Getting the data from snapshot
            //AppInfo appInfo = postSnapshot.getValue(AppInfo.class);
            Log.v(Constants.TAG, "postSnapshot " + dataSnapshot.getChildren());
        }

        @Override
        public void onChildMoved(DataSnapshot dataSnapshot, String s) {


            Log.v(Constants.TAG, "FireBaseCalled 44");
            //Getting the data from snapshot
            //AppInfo appInfo = postSnapshot.getValue(AppInfo.class);
            Log.v(Constants.TAG, "postSnapshot " + dataSnapshot.getChildren());
        }

        @Override
        public void onCancelled(FirebaseError firebaseError) {


        }

    });

}

Answer 1

你走了。！希望这对你有帮助。！

import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;

public class MainActivity extends AppCompatActivity
{
          private FirebaseDatabase mdatabase;

            private DatabaseReference mdatabaseRef;
 public static List<AppInfo > appInfo_list =new ArrayList<>();

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.Main_Activity);

           initFirebase();

        AddEventFireBaseListner();


}



    public void initFirebase() {
        mdatabase = FirebaseDatabase.getInstance();
        mdatabaseReference = mdatabase.getReference();
        // storageRef = FirebaseStorage.getInstance().getReference();
    }





 public void AddEventFireBaseListner() {


     mdatabaseRef.child("AppInfo").addValueEventListener(new ValueEventListener() {
                    @Override     
                    public void onDataChange(DataSnapshot dataSnapshot) {

                        Log.e(TAG, "AppInfoNode:");


     if (appInfo_list.size() > 0)
                appInfo_list.clear();



           for(DataSnapshot postSnapshot:dataSnapshot.getChildren())
               {


        AppInfo appInfo= postsnapshot.getValue(AppInfo.class);



               if(postSnapshot.getKey().equals("AppName"))
            {
                  Log.e(TAG, "NodeSnapShot:");


            String AppNameStr=postSnapshot.getValue().toString();

             Log.e(TAG, "AppName:"+AppNameStr);


          }



                   if(postSnapshot.getKey().equals("VersionName"))
                    {
                          Log.e(TAG, "VersionName:");


                    String VersionName=postSnapshot.getValue().toString();

                     Log.e(TAG, "VersionName:"+VersionName);


                  }


            if(postSnapshot.getKey().equals("VersionCode"))
                    {
                          Log.e(TAG, "VersionCode:");


                    String VersionCode=postSnapshot.getValue().toString();

                     Log.e(TAG, "VersionCode:"+VersionCode);




                  }//end of if 

                appInfo_list.add(appInfo);

          //  AppInfo modelClass=new AppInfo ();
          //  modelClass.setAppName(AppNameStr);
         //   modelClass.setAppVersionName(VersionName);
        //    modelClass.setAppVersionCode(VersionCode);


                    }

    }

在每个节点循环结束时，您可以将其存储在ModelClass对象中。！

如何在没有setValue的情况下获取Firebase数据库整个节点？

1 个答案: