Solution:
I have to use snap.value. now I had tried "snap.children" which works fine. In the same query snap.value return unsorted data snap.children return sorted data
self.referenceData = (Database.database().reference().child("imagelist" + "/" + userID!))
self.referenceData.queryOrdered(byChild: "created").observeSingleEvent(of: .value, with: { (snap : DataSnapshot) in
print(snap.value) // Unsorted
print(snap.children) // Sorted
...
})
PROBLEM
I am trying to sort the data by created the key. but nothing happened, maybe any mistake in my code,
self.referenceData = (Database.database().reference().child("imagelist" + "/" + userID!))
self.referenceData.queryOrdered(byChild: "created").observeSingleEvent(of: .value, with: { (snap : DataSnapshot) in
...
})