Android Firebase ..我如何检索数据

Question

我需要我的简单应用程序的帮助。我在我的应用程序中添加了点功能，并且还添加了Firebase。但是如何将点从Firebase恢复到同一位置？

Answer 1

你可以尝试这样的事情。我正在检索像这样的所有应用用户

FirebaseDatabase database = FirebaseDatabase.getInstance(); 
    DatabaseReference myRef = database.getReference("users"); 
    myRef.addValueEventListener(new ValueEventListener() { 
      @Override 
      public void onDataChange(DataSnapshot dataSnapshot) { 
       userList = new ArrayList<User>(); 
       dataSnapshot.getChildrenCount(); 
       //List<User> list= new ArrayList<User>(); 
       for (DataSnapshot childDataSnapshot : dataSnapshot.getChildren()) { 
        User user = childDataSnapshot.getValue(User.class); 
        userList.add(user); 
       } 
       Log.e("hello","childDataSnapshot"+ userList.size()); 

       adapter.update(userList); 

      } 

      @Override 
      public void onCancelled(DatabaseError error) { 
       // Failed to read value 
       Log.w("MY", "Failed to read value.", error.toException()); 
      } 
     });