在android中获取父节点firebase

Question

这是我当前的代码。我怎样才能获得头名的父节点

final Query userQuery = mRef.orderByChild("First Name"); 

    userQuery.addChildEventListener(new ChildEventListener() { 
     @Override 
     public void onChildAdded(DataSnapshot dataSnapshot, String s) { 
      map.clear(); 
      for (DataSnapshot child: dataSnapshot.getChildren()) 
      { 
       String key = child.getKey().toString(); 
       String value = child.getValue().toString(); 
       map.put(key,value); 
      } 

Answer 1

你应该调用getKey()方法您检索dataSnapshot：

final Query userQuery = mRef.orderByChild("First Name"); 

    userQuery.addChildEventListener(new ChildEventListener() { 
    @Override 
    public void onChildAdded(DataSnapshot dataSnapshot, String s) { 
     map.clear(); 
     //Get the node from the datasnapshot 
     String myParentNode = dataSnapshot.getKey(); 
     for (DataSnapshot child: dataSnapshot.getChildren()) 
     { 
      String key = child.getKey().toString(); 
      String value = child.getValue().toString(); 
      map.put(key,value); 
     }