DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference usersRef = rootRef.child("Users");
ValueEventListener eventListener = new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
ListView listView = (ListView) rootView.findViewById(R.id.usersList);
ArrayAdapter<String> adapter;
adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, android.R.id.text1, al);
for(DataSnapshot ds : dataSnapshot.getChildren()) {
name = ds.child("Name").getValue().toString();
phonenumber=ds.getKey();
list_user_id = getRef(position).getKey;
// Log.d("TAG", name);
al.add(name);
}
listView.setAdapter(adapter);
}
@Override
public void onCancelled(DatabaseError databaseError) {
Toast.makeText(getActivity(),"Please Check Your Internet Connection",Toast.LENGTH_SHORT).show();
}
};
usersRef.addListenerForSingleValueEvent(eventListener);
我有一个所有用户活动...如果我点击一个用户我想获取他们的唯一ID但我无法做到这一点...行中的错误 - list_user_id = getRef(position).getKey;是我的错误取错方法还是方法过时了?
答案 0 :(得分:1)
由于您有列表视图,因此可以执行以下操作:
lists.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
final String selectedFromList = (String)lists.getItemAtPosition(i);
db= FirebaseDatabase.getInstance().getReference().child("Users");
db.orderByChild("username").equalTo(selectedFromList).addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot data: dataSnapshot.getChildren()){
String ids=datas.getKey();
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
});
假设你有一个包含用户名的listview,并假设你在db中有这个:
Users
userid
username://name
userid
username: //name
使用此final String selectedFromList = (String)lists.getItemAtPosition(i);
,您可以在这种情况下获取username
的项目。然后使用查询equalTo()
它将检查数据库并使用getKey()
答案 1 :(得分:0)
您可以使用onDataChange方法中的Map来获取Firebase数据库中的所有键值,如下所示:
Map<String, Object> td = null;
for (com.google.firebase.database.DataSnapshot postSnapshot : dataSnapshot.getChildren()) {
td = (HashMap<String, Object>) postSnapshot.getValue();
String userName= (String) td.get("userName");
String mobileNUM= (String) td.get("mobileNUM");
}