Launching a window from a worker thread? Please Help

me 0

Please, i really need help. Im doing a project for my 4th year of college, its going perfect, until now. Its an instant messaging program. A thread is started when you logon called incomingMessage. incomingmessage loops, listening for an incoming message, when it receives one, it processes it, if its an alert or a message (an "instant message") it passes it back to the main program, via a delegate. however, i cant make an IM Window popup no matter what i do. it seems its still a different thread, and only the GUI thread can sucessfully create windows. I CAN create a window by making its default constructor begin in another new thread, and kick off a modal (dialog) version of itself (this.ShowDialog(null) ), it works, to an extent, but its not the way to go, the thread is waiting for the window to close, and its just messy and definitly NOT the solution for more than one IM window. Does anyone have any ideas on how to get the GUI thread to know a message has arrived, and let it open up the window itself? I tried events, flags etc, but any event delegate seems to be operating in its own thread. Im about to go home and try MSMQ (Message Queueing) to see if that'll work. Does anyone have any ideas? Would greatly appreciate the help Thank you

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me 021y ago
Thanks for the reply, but i fixed it :-)))))))) When looking at message queueing, i came across timers, which ive always known about but never actually used. Anyway, when a message arrives, the incomingmessage thread places it in a queue and raises a flag. the Main thread has a timer which is checking for newly arrived mesages in the queue (by checking the flag) every 250ms. If it sees one, it can then look at it, decide what kind of message it is, and if necessary, open an Im Window (yes, its an array of Im windows) I have a static class called ChatWindowManager which allocates window IDs to Chat Windows, and monitors which windows are in use. It also handles messaging to and from the main window to these chat windows. So t works, thanks again for your reply, I was driven mad with it. At the moment, the queue is just a Message variable (a class i wrote) and the flag is just a bool. I will make the queue an array of Messages and the flag an Int, which'll contain 0 if no messages, 1 if one message etc. So im back on track again. Thanks. :-)
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fixme21y ago
Greetings. I take it that your mainform contains an array/collection of forms that you are using for IM windows. Have you tried having your mainform have a thread that only listens for requests for new IM sessions, and sends outgoing messages? Your GUI thread can spawn them as needed and keep inventory on the windows being used. Since the GUI thread would be creating the IM windows, you can route messages to them via unique ID the instance contains and from them via events. You'd have to spinlock during the message event handlers, so that you can set flags for the message thread to check and dump the message into the pool. This is just off the top of my head, so I might have missed something. Hope this helps.
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