Android 我希望Firebase实时数据库在内部更新
我有这样一个数据库: 我想在firebase DB中将cityIdealScore的值自动更新为“cityTop*10+cityWin”,但我不知道怎么做 p、 我需要cityealscore的值来按分数查询数据库 p、 s.2Android 我希望Firebase实时数据库在内部更新,android,firebase,firebase-realtime-database,Android,Firebase,Firebase Realtime Database,我有这样一个数据库: 我想在firebase DB中将cityIdealScore的值自动更新为“cityTop*10+cityWin”,但我不知道怎么做 p、 我需要cityealscore的值来按分数查询数据库 p、 s.2 public void fbWinUpdate(int cityNum) { String cNum = String.valueOf(cityNum); databaseReference.child(cNum).runTransaction(new
public void fbWinUpdate(int cityNum) {
String cNum = String.valueOf(cityNum);
databaseReference.child(cNum).runTransaction(new Transaction.Handler() {
@Override
public Transaction.Result doTransaction(MutableData mutableData) {
CityDetails cd = mutableData.getValue(CityDetails.class);
if(cd == null) {
return Transaction.success(mutableData);
}
cd.cityWin = cd.cityWin + 1;
mutableData.setValue(cd);
return Transaction.success(mutableData);
}
@Override
public void onComplete(DatabaseError databaseError, boolean b, DataSnapshot dataSnapshot) {
Log.d("DBError", "postTransaction:onComplete:" + databaseError);
}
});
}
public void fbTopUpdate(int cityNum) {
String cNum = String.valueOf(cityNum);
databaseReference.child(cNum).runTransaction(new Transaction.Handler() {
@Override
public Transaction.Result doTransaction(MutableData mutableData) {
CityDetails cd = mutableData.getValue(CityDetails.class);
if(cd == null) {
return Transaction.success(mutableData);
}
cd.cityTop = cd.cityTop + 1;
mutableData.setValue(cd);
return Transaction.success(mutableData);
}
@Override
public void onComplete(DatabaseError databaseError, boolean b, DataSnapshot dataSnapshot) {
Log.d("DBError", "postTransaction:onComplete:" + databaseError);
}
});
}
public void fbTop4Update(int cityNum) {
String cNum = String.valueOf(cityNum);
databaseReference.child(cNum).runTransaction(new Transaction.Handler() {
@Override
public Transaction.Result doTransaction(MutableData mutableData) {
CityDetails cd = mutableData.getValue(CityDetails.class);
if(cd == null) {
return Transaction.success(mutableData);
}
cd.cityTop4 = cd.cityTop4 + 1;
mutableData.setValue(cd);
return Transaction.success(mutableData);
}
@Override
public void onComplete(DatabaseError databaseError, boolean b, DataSnapshot dataSnapshot) {
Log.d("DBError", "postTransaction:onComplete:" + databaseError);
}
}); }
这是我的城市地图,城市地图,城市地图4的更新代码。我想我可以用这种方法计算分数,但我认为它是无效的。我想知道我是否能在FirebaseRules上计算分数,诸如此类这就是你可以做到的:
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference ref = rootRef.child("City_Details_Database");
ValueEventListener eventListener = new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds : dataSnapshot.getChildren()) {
Integer cityTop = ds.child("cityTop").getValue(Integer.class);
Integer cityWin = ds.child("cityWin").getValue(Integer.class);
Integer cityIdealScore = cityTop*10 + cityWin;
dataSnapshot.child("cityIdealScore").getRef().setValue(cityIdealScore);
Log.d("TAG", valueToUpadate);
}
}
@Override
public void onCancelled(DatabaseError databaseError) {}
};
ref.addListenerForSingleValueEvent(eventListener);
分享你的代码我对此一无所知,所以我没有任何代码,但我有一个关于更新cityTop,cityTop4,cityWin@RedGod你想什么时候发生?在某些用户操作或数据库数据插入、删除、更新?我希望在firebase中进行实时更新