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Update Group

In other words, as a group owner, how can I update the group details? You can update the existing details of the group using the updateGroup() method. 
let GUID = "GUID";
let groupName = "Hello Group!";
let groupType: CometChat.groupType = .public;

let groupTobeUpdated = Group(guid: GUID, name: groupName, groupType: groupType, password: nil)

CometChat.updateGroup(group: groupTobeUpdated, onSuccess: { (group) in

  print("Groups details updated successfully. " + group.stringValue())

}) { (error) in

   print("Group details update failed with error: " + error!.errorDescription);
}
This method takes an instance of the Group class as a parameter that should contain the data that you wish to update.
ParameterDescription
groupan instance of class Group
After a successful update of the group, you will receive an instance of the Group class containing update information of the group.