I am trying to get some random posts from Firebase. But i am unable to get random document id.
Is there any way to retrieve data from Firebase like this :-
getRandomData() async { QuerySnapshot snapshot = await posts .document(random.id) .collection('userPosts') .getDocuments();} 
i am trying to say that. Now i am able to get documentID normally not in italics.so now how can i get random documentID from Firebase.
List documentIds in a list first.
var list = ['documentId1','documentId2','documentId3'];
var element = getRandomElement(list);
Then query the documentSnapshot
The main problem here that's going to prevent you from moving forward is the fact that you don't actually have any documents nested immediately under "posts". Notice that the names of the documents are in italics. That means there isn't actually a document here at all. The reason why they are show, however, is because you have a subcollection "userPosts" nested under the path where that document ID exists.
Since you don't have any documents at all under "posts", the usual strategies to find a random document won't work at all. You're going to have to actually populate some data there to select from, or find another way to select from the data in the subcollections.
You can first get all documents in you collection.
Try this code:
async getMarker() { const snapshot = await firebase.firestore().collection('userPosts').get(); const documents = []; snapshot.forEach(doc => { documents[doc.id] = doc.data(); }); return documents; } Next, from return documents you can create a list of documents id and get random numbers (document id) from this list.
firestore() .collection('SOURCE') .doc(props?.route?.params?.data?.id) .collection('userPosts') .get() .then(querySnapshot => { querySnapshot.forEach(documentSnapshot => { console.log('User ID: ', documentSnapshot.id, documentSnapshot.data()); }) })
