Flutter and Firebase: Return all images from Firebase Storage - firebase

Question

I have seen a few articles written online by people pertaining to be able to do this, but they only tell you how to do this with a specific, controlled list of images where they also know all the filenames beforehand.
There is also this "answer" posted here: Flutter - Get all images from firebase storage which does not actually resolve this issue at all as it suggests a .listAll() method for the recommended plugin, but there is no such method as .listAll() using the suggested plugin.
I need to be able to not know how many images are in Firebase storage, or what they might be called, just to return everything stored there.
UPDATE:
So because Firebase is full of so many limitations that it hardly qualifies as a database at all, it seems we may have to keep the images in Firebase Storage and a reference list of these in a Firebase Realtime Database Document.
I am stuck on the actual implementation of this however, as I am not even sure firstly how best to go about this. What I am attempting to do is store all the Storage image URLs in an array (if this is not the best way to do this, let me know!):
Firebase Structure
collection -> document -> fields
userData profileImages URLs (array)
My first issue is that I don't know how to append new data to the existing array, it seems to just overwrite it each time I add a new item so that I only ever have one string in the array in the database:
Firestore.instance.collection('userData').document('profileImages').updateData({
'URLs': _uploadedFileURL,
});
Then after this I am also not sure how to actually retrieve the full array of data later when I need it:
Container(
child: StreamBuilder(
stream: Firestore.instance.collection('userData').document('profileImages').snapshots(),
builder: (BuildContext context, AsyncSnapshot<DocumentSnapshot> snapshot) {
if (!snapshot.hasData) {
return LoadingAnimationBasic();
}
if (snapshot.data.data == null) {
return LoadingAnimationBasic();
} else {
return ListView(
shrinkWrap: true,
children: _buildProfileGallery(snapshot),
);
}
},
),
),
And then the function:
_buildProfileGallery(AsyncSnapshot<DocumentSnapshot> snapshot) {
int test = snapshot.data["URLs"].length;
print('URLs in List: ' + test.toString());
return snapshot.data.data.map(???);
}
I have no idea what to put as the parameters of this map, as the hint text is insane:
MapEntry(K2, V2> f(String key, V value)
I can't even begin to guess what this means.
Am I on the right track? Am I on the right planet?

Answer 1

The ability to list files was added to Firebase's client-side SDKs for Android, iOS and JavaScript last year, but has not yet landed in the FlutterFire bindings.
The answer to the question you linked, refers to a pull request on the FlutterFire open-source project that adds this functionality. So while somebody wrote code to allow listing of files in Flutter too, this code hasn't been added to a release so far. So the only way to use that code now, is to build your own version of the FlutterFire library for firebase_storage.
Without the ability to list files in the Firebase Storage API, you'll have to revert back to what everyone did before this feature was added: keeping a list of the files in a secondary location, such as the Firebase Realtime Database or Cloud Firestore.