How to get an array from Firestore?

Question

I have the data structure illustrated below stored in Cloud Firestore. I want to save the dungeon_group which is an array of strings stored in Firestore.

I have difficulty in getting the data and stored as an array. I am just able to get a weird string but any method to store as a string array? Below is the code I used.

I am able to achieve this in Swift as follow, but not sure how to do the same in Android.

Swift:

Firestore.firestore().collection("dungeon").document("room_en").getDocument {      (document, error) in     if let document = document {         let group_array = document["dungeon_group"] as? Array ?? [""]         print(group_array)     }     } 

Java Android:

FirebaseFirestore.getInstance().collection("dungeon")                  .document("room_en").get()                  .addOnCompleteListener(new                       OnCompleteListener<DocumentSnapshot>() {                      @Override                      public void onComplete(@NonNull Task<DocumentSnapshot> task) {                          DocumentSnapshot document = task.getResult();                          String group_string= document.getData().toString();                          String[] group_array = ????                          Log.d("myTag", group_string);                      }                  }); 

Console output as the follow:

{dungeon_group=[3P, Urgent, Mission Challenge, Descended, Collaboration, Daily, Technical, Normal]}

Answer 1

When you call DocumentSnapshot.getData(), it returns a Map. You're just calling toString() on that map, which is going to give you a dump of all the data in the document, and that's not particularly helpful. You need to access the dungeon_group field by name:

DocumentSnapshot document = task.getResult(); List<String> group = (List<String>) document.get("dungeon_group"); 

• edit: syntax error in typecasting