#Flutter firebase chat app how to
#Flutter firebase chat app code

#Flutter firebase chat app how to

I would appreciate any guidance on how to approach this task.įirst of all the question is, the badge number represents the number of unread conversations or unread total number of messages in the conversations (all of them combined)? I will determine the unread count by checking the number of instances of where the currentUser id is contained in the 'last_message_seen_by' field. I am not sure if my Stream approach is correct, and I don't know how to parse the above result so I can determine the unread count. where('users', arra圜ontains: currentUserReference)įlutter: I am getting the data, but I am having a challenge parsing it so I can determine the unread count.

#Flutter firebase chat app code

Here is the code that I used to create the Stream. I tried to create a Stream but run into challenges implementing that approach. I know how to determine the unread count from my chat collection, but I am not sure of the most effective way to get the data. I am using Badges to place a number alongside the Messages icon, but I am not sure of the best way to determine the unread message count from the Chats collection in Firestore. I have the app working but I am having difficulty implementing the unread message counter to feed the Navbar. Note: if your app will support user log-off, then you'll also have to delete the token in the device to avoid receiving notifications from the last logged user.I am building a simple chat app using Flutter and Firestore.

In the flutter code, you can use subscribeToTopic from the firebase_messaging plugin to start listening to a topic. In this answer you have an example of how to post the notifications with a onCreate trigger to a topic (from a functions backend). (but add that later so you don't get distracted with non core stuff) If that wouldn't be an issue, then just go for just one topic per chatroom.Īlso mentioning Frank, I would probably use extra keys in all topic names to make them really difficult to guess. I would probably use that as the chat key in the database (realtime/firestore), however, for the notifications I think I would still use a topic for each user - this way I would be able to avoid notifying the user who posted the message. I found Frank's comment really interesting about the 'sorted userID composed key'.

With your current Firestore implementation you can query the database to get all messages to show, while with a pure FCM implementation you will have to build your own database (if that is required for your app).įor these reasons most chat apps I know of use a combination of FCM (for push notifications) and an online database (for persistence) as their backend services. And while you can generate topics that are hard to guess, you should not rely on not knowing the topic ID as a security mechanism.Īnother reason to consider alternatives is that FCM messages are transient: once they are delivered there is no longer any trace of them.

This means that anyone who finds out the topic ID can subscribe to it, and thus overhear the 1:1 conversation. But there are some things to consider which, as Doug already pointed out in his comment, leads most developers to not solely use FCM for their chat apps.įor example: FCM topics are not secured. You can definitely use a separate topic for each 1:1 conversation, for example with the naming scheme I described here: Best way to manage Chat channels in Firebase.