Retrieve Groups - CometChat Docs

AI Integration Quick Reference

Field	Value
Package	`cometchat_sdk`
Import	`import 'package:cometchat_sdk/cometchat_sdk.dart';`
Purpose	Fetch CometChat groups in Flutter apps with pagination, search keywords, joined-only filters, tags, and group request builders.
Key methods	`getGroup()` · `getOnlineGroupMemberCount()`
Key classes	`Group` · `CometChatException`
Prerequisites	SDK initialised via `CometChat.init()` and a logged-in user via `CometChat.login()`.
Constraints	`onSuccess` and `onError` are both required — omitting either is a compile error, and awaiting the call alone gives you nothing to act on. Put the success path inside `onSuccess`.
Related	Groups · Join A Group
Full reference	`Group` · `CometChatException`

Retrieve List of Groups

In other words, as a logged-in user, how do I retrieve the list of groups I’ve joined and groups that are available? In order to fetch the list of groups, you can use the GroupsRequest class. To use this class i.e to create an object of the GroupsRequest class, you need to use the GroupsRequestBuilder class. The GroupsRequestBuilder class allows you to set the parameters based on which the groups are to be fetched.

Set Limit

This method sets the limit i.e. the number of groups that should be fetched in a single iteration.

Dart

GroupsRequest groupsRequest =  (GroupsRequestBuilder()
  ..limit= 20
).build();

Set Search Keyword

With offline support on, this filter is answered by the server only; the cached page is empty.

This method allows you to set the search string based on which the groups are to be fetched.

Dart

GroupsRequest groupsRequest =  (GroupsRequestBuilder()
  ..limit= 20
  ..searchKeyword = "abc"  
).build();  

Joined Only

This method when used, will ask CometChat to only return the groups that the user has joined or is a part of.

Dart

GroupsRequest groupsRequest =  (GroupsRequestBuilder()
  ..limit= 20
  ..joinedOnly = true
).build();

Set Tags

This method accepts a list of tags based on which the list of groups is to be fetched. The list fetched will only contain the groups that have been tagged with the specified tags.

Dart

List<String> tags =[];
tags.add("archived");
GroupsRequest groupsRequest =  (GroupsRequestBuilder()
  ..limit= 20
   ..tags = tags
).build();

With Tags

This property when set to true will fetch tags data along with the list of groups.

Dart

GroupsRequest groupsRequest =  (GroupsRequestBuilder()
  ..limit= 20
  ..withTags = true
).build();

Finally, once all the parameters are set to the builder class, you need to call the build() method to get the object of the GroupsRequest class. Once you have the object of the GroupsRequest class, you need to call the fetchNext() method. Calling this method will return a list of Group objects containing ‘n’ number of groups depending on the limit set. The list of groups fetched will only have the public and password type groups. The private groups will only be available if the user is a member of that private group.

Starting with v5.1.0, `fetchNext()` accepts a listener: parameter. Pass a `GroupFetchListener` to receive the on-device cached result. The listener: parameter requires cometchat_sdk 5.1.0 or later, so on 5.0.x keep using onSuccess/onError. With offline support off, the listener behaves exactly like the callbacks: onError is unchanged, and the server result arrives in the onServer… callback instead of onSuccess. With offline support on, the listener also delivers the cached result first, then the server result. onSuccess/onError keep working and receive only the server result. See Show Cached Data.

Dart

class Class_Name extends GroupFetchListener {
  @override
  void onCachedGroups(List<Group> groups) {
    // Cached page: fires first (even when empty). Render immediately.
    debugPrint("Cached groups: ${groups.length}");
  }

  @override
  void onServerGroups(List<Group> groups) {
    // Server page: reconcile your displayed list, keyed by guid.
    debugPrint("Server groups: ${groups.length}");
  }

  @override
  void onError(CometChatException e) {
    // Handle failure (offline: ERR_CONNECTION after the cached page).
    debugPrint("Group Request failed with exception: ${e.message}");
  }
}

GroupsRequest groupsRequest =  (GroupsRequestBuilder()
  ..limit= 20
).build();

groupsRequest.fetchNext(onSuccess: null, onError: null, listener: Class_Name());

Retrieve Particular Group Details

In other words, as a logged-in user, how do I retrieve information for a specific group? To get the information of a group, you can use the getGroup() method.

Dart

String GUID = "GUID";

CometChat.getGroup(GUID, onSuccess: (Group group) {
      debugPrint("Fetched Group Successfully : $group ");
    }, onError: (CometChatException e) {
      debugPrint("Group Request failed with exception: ${e.message}");
    });

Parameter	Description
`GUID`	The GUID of the group for whom the details are to be fetched

On success, the Group object containing the details of the group is returned.

Get online group member count

To get the total count of online users in particular groups, you can use the getOnlineGroupMemberCount() method.

Dart

List<String> guids =  [];
guids.add("cometchat-guid-1");
guids.add("cometchat-guid-11");

CometChat.getOnlineGroupMemberCount(guids,
        onSuccess: (Map<String, int> count) {
      debugPrint("Fetched Online Group Member Count Successfully : $count ");
    }, onError: (CometChatException e) {
      debugPrint("Online Group Member failed with exception: ${e.message}");
    });

This method returns a Map with the GUID of the group as the key and the online member count for that group as the value.

Offline Behaviour

With offline support enabled, GroupsRequest.fetchNext() with a GroupFetchListener first delivers onCachedGroups from the device (empty when nothing was recorded), then onServerGroups with the live page to reconcile by guid. Offline, the read ends with onError with code ERR_CONNECTION (details ERROR_INTERNET_UNAVAILABLE) after the cached page. A request that uses a server-only filter records nothing, so its cached page is always empty. See Show Cached Data.

Builder option	Offline
`limit`	Cached
`joinedOnly`	Cached
`tags`	Cached
`withTags`	Cached
`searchKeyword`	Server only — cached page is empty

​Retrieve List of Groups

​Set Limit

​Set Search Keyword

​Joined Only

​Set Tags

​With Tags

​Retrieve Particular Group Details

​Get online group member count

​Offline Behaviour

Retrieve List of Groups

Set Limit

Set Search Keyword

Joined Only

Set Tags

With Tags

Retrieve Particular Group Details

Get online group member count

Offline Behaviour