Firebase 搜索不同字段时从一个字段获取值

Question

As of right now I am using firebase to get a user in a "users" collection like this:

val query: Query = usersCol.whereEqualTo(USERNAME_KEY, usernameInput)

USERNAME_KEY is a string "username" which is the same as in the database

usernameInput is the username of the user I'm getting from the database

(The primary key is an id that I can't search for) Is it possible to get the value this primary key? or other fields in the same "level" as username, like 'name' or 'password'

I'm imagining something like:

   query.get("id")

but that doesn't work...

Answer 1

You will need to execute the query before you can get results from it. As shown in the Firebase documentation you can execute a query like this:

query
    .get()
    .addOnSuccessListener { documents ->
        for (document in documents) {
            Log.d(TAG, "${document.id} => ${document.data}")
        }
    }
    .addOnFailureListener { exception ->
        Log.w(TAG, "Error getting documents: ", exception)
    }

Within that loop, you can get a specific field from the document with:

document.get("name")