在通过多次查询从Firebase检索正确的信息时出现问题 [英] Having issue retrieving correct information from Firebase with multiple lookups
问题描述
下面是我实现的代码，该代码可以工作，但是当它们的最后三个Firebase子对象"PoolName"和"PoolId"不同时，它们将它们分配给所有三(3)个结果！?
Below is the code I implemented which works but its assigning the last Firebase child 'PoolName' and 'PoolId' to all three (3) results when they should be different!?
playerInPoolReference = mFirebaseDatabase.getReference("PlayerInPool").child(userID);
playerInPoolReference.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
if(dataSnapshot.exists()) {
for (DataSnapshot poolSnapshot : dataSnapshot.getChildren()) {
String poolID = poolSnapshot.getKey();
poolReference = mFirebaseDatabase.getReference("Pools").child(poolID);
poolReference.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snapShot) {
if (snapShot.exists()) {
pID = snapShot.getKey();
String gameID = snapShot.child("GameId").getValue().toString();
//
pName = snapShot.child("PoolName").getValue().toString();
gameReference = mFirebaseDatabase.getReference("Games").child(gameID);
gameReference.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot snap) {
if (snap.exists()) {
Pools pool = snap.getValue(Pools.class);
pool.setPoolId(pID);
pool.setPoolName(pName);
//
poolList.add(pool);
adapter = new PoolAdapter(getActivity(), poolList);
recyclerView.setAdapter(adapter);
}
}
@Override
public void onCancelled(@NonNull DatabaseError error) {
}
});
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
} // End for loop
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
有人知道或已经实施了一个解决方案，以使我希望获得特定用户所在的组(例如我的池)的列表吗?
Does anyone know or have they implemented a solution where I wish to get the list of Groups (ex. Pools in my case) that a particular user is in?
在我的情况下，我检查玩家所在的池，然后需要访问池节点以获取池信息，其中包括特定的游戏ID，然后最后获取关联的游戏信息，以便我可以显示给玩家.
In my case I check for the pools that the player is in, then need to access the Pool Node to get the Pool info, which included the particular game id , and then lastly get the associated Game info so that I can display to the player.
Firebase的结构如下:
The Firebase structure is as follows:
Users
userId1
userName : peter
userId2
userName : john
Pools
poolId1
poolName: pool1
etc....
poolId2
poolName: pool2
Games
1000
gameName: game1
1001
gameName: game2
PlayerInPool
UserId
12345: true
54321: true
etc...
UserId:
12345: true
问题在于它设置了以下内容:
The ISSUE is that it sets the following:
pool.setPoolId(pID);
pool.setPoolName(pName);
到池列表中的最后一个值！?
to the last values in the list of pools!?
推荐答案
Users
userId1
userName : peter
userId2
userName : john
Pools
poolId1
poolName : pool1
poolId2
poolName : pool2
Games
gameId1
gameName : game1
gameId2
gameName: game2
UserPool
poolId1
userName: peter
poolId2
userName: john
GamePool
gameId
poolId: poolId1
gameName : game1
您可以执行以下数据库，其父节点包括Users，Pools和Games.然后，您可以做两个节点，一个叫UserPool，可以包含每个池中的所有用户，另一个叫GamePool，可以包含游戏名称和池信息.
You can do the following database, parent node including Users, Pools, and Games. Then you can do two nodes, one called UserPool that can include each all the users that are in each pool, and the other called GamePool that can include game name and pool info.
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference userReference = database.getReference("UserPool");
DatabaseReference gameReference = database.getReference("GamePool");
userReference.orderByKey().equalTo(poolId).addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds: dataSnapshot.getChildren()){
String keyPool = ds.getKey();
String userId = ds.child("userName").getValue().toString();
gameReference.orderByChild("poolId").equalTo(keyPool).addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot datas : dataSnapshot.getChildren()){
String gameId = datas.getKey();
String gameName = datas.child("gameName").getValue().toString();
}
}
@Override
public void onCancelled(DatabaseError databaseError) {}
});
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
在此处将引用放在子级UserPool上并检索poolId和userNames，还可以添加其他信息并在此处检索它们.
Here you put the reference at child UserPool and retrieve the poolId and the userNames, you can also add other info and retrieve them here.
然后，您使用引用节点gamePool的嵌套valueEventListener，并使用检索到的键(即poolId)创建查询和orderByChild("poolId").equalTo(keyPool)并检索游戏名称，以及您可以在其中添加的其他信息，例如游戏信息...
Then you use a nested valueEventListener that refers to the node gamePool and using the key that you retrieved (which is the poolId), you create a query andorderByChild("poolId").equalTo(keyPool) and retrieve the game name, and other info that you can add there like game info...
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