这是我在
Android应用程序中使用时间戳的firebase数据的简单查询
Query recentStaticJobQuery = reference.child(AppConstants.WORKINDIA_JOBS)
.child(AppConstants.WORKINDIA_STATIC_JOBS)
.orderByChild(AppConstants.TIMESTAMP)
.startAt(lastStaticJobSyncTime);
recentStaticJobQuery.addListenerForSingleValueEvent
(staticJobDownloadListener);
ValueEventListener staticJobDownloadListener = new ValueEventListener() {
@Override
public void onDataChange(final DataSnapshot dataSnapshot) {
Log.i("Firebase","Called")
}
@Override
public void onCancelled(DatabaseError databaseError) {
Log.i("Firebase","onCancelled")
}
};
如何避免onDataChange在android Firebase中被调用两次？
解决方法
使用SingleEventListener而不是ValueEventListener像这样
Firebase ref = new Firebase("YOUR-URL-HERE/PATH/TO/YOUR/STUFF");
ref.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
String value = (String) dataSnapshot.getValue();
// do your stuff here with value
}
@Override
public void onCancelled(FirebaseError firebaseError) {
}
});
