Updating an arraylist of objects in Firestore

Asked Mar 21 '19 at 02:31

Active Mar 21 '19 at 02:40

Viewed 144 times

I have an array list of objects and I want to update my array-list with new data but, I get an error "Could not deserialize object. Expected a List, but got a class java.util.HashMap (found in field 'students')"

here's my database

Here's the method that's responsible for updating the arraylist

   private void update(){
    Map<String, Object> updatedlist = new HashMap<>();
    for(int i=0; i<studentsList.size(); i++){
        updatedlist.put("name", studentsList.get(i).getName());
        updatedlist.put("id", studentsList.get(i).getId());
        updatedlist.put("attended", studentsList.get(i).isAttended());
    }
    DocumentReference document = db.collection("Records").document(rid);
    document.update("students", updatedlist);
}

for clarification, studentslist is an arraylist of students object ( List < students > studentslist ) I tried converting the array-list to a hash-map as well as updating the list as an array-list but I got an error from both ways.

edited Mar 21 '19 at 02:40

asked Mar 21 '19 at 02:31

Skeptic94

Please check the duplicate to see how you can update a property of type array. – Alex Mamo Mar 21 '19 at 07:11
It may seem a duplicate but, in my case I want to update the whole array not just array elements. :( – Skeptic94 Mar 21 '19 at 09:51
In that case you should try to add a list to the database and **not** a map. – Alex Mamo Mar 21 '19 at 10:00
I did and I got an error " Invalid data. Unsupported type: Models.students" – Skeptic94 Mar 21 '19 at 10:08

Updating an arraylist of objects in Firestore

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