Question

i’m developing a microsoft WPF instant message application based on XMPP using agsXMPP library. there are many events in the agsXMPP like OnXmppConnectionStateChanged,OnLogin,OnPresence and so on, and on the other hand, because of the WPF thread mode, i have to handle event through UI’s Dispatcher.Invoke() method,it exactly looks like this:

    void handleRosterItem(object sender, agsXMPP.protocol.iq.roster.RosterItem item)
    {
        STP_FriendsHolder.Dispatcher.BeginInvoke(new Action(delegate
        {
            RosterItemControl rosterItem = new RosterItemControl();
            rosterItem.RosterItemName = item.Jid.User;
            rosterItem.Margin = new Thickness(0);
            STP_FriendsHolder.Children.Add(rosterItem);
        }));
    }

i use anonymous method in almost every BeginInvoke/Invoke method,because i don’t want to create too many named methods everywhere(as i think this is not so ‘clean’). But i’m afraid it’s not so in a OOP way, and these anonymous methods are very difficult to maintain. So,how can i code in a better way in this situation?
i’m sorry for my poor English,i have tried my best to make it clear^_^
thanks！

Answer 1

1. I would not be handling the XMPP events in your code-behind class. Create a class that is responsible just for handling the events.
2. Create an interface this class will consume with nice clean methods for translating the XMPP events, e.g. NewRosterItem(RosterItem item)
3. Call these methods by invoking on the dispatcher (i.e. encapsulate the BeginInvoke just to the class that handles the events.
4. Have your view implement the interface and register with the event handling class, they can then create and update whatever controls are necessary.