2011/5/2 Michael Schnell <[email protected]>:
> PostMessage() and QueueAsyncCall() _should_ work.
PostMessage() works (that is what I currently use) and
QueueAsyncCall() did not work when I opened this thread, I will test
it again tomorrow.
But what I would need for my application is something like
Synchronize(), I need to block my camera thread after every frame
until the GUI has updated itself with the newly received frame.
Therefore I have now re-implemented the functionality of Synchonize()
in the following way:
// normally I would have used Synchoize() here but this
// does not work with the really old GTK2 I have here anymore,
// it would not wake up the GUI thread until I move the mouse.
// The following 3 lines together with the message method in the
// main form do exactly the same. It wakes up the GUI thread and
// waits until it is done.
RTLeventResetEvent(GuiHasFinishedEvent);
PostMessage(Application.MainForm.Handle, MM_FRAME_COMPLETE, 0, 0);
RTLeventWaitFor(GuiHasFinishedEvent);
and in the GUI
TMainForm = Class(TFom)
...
procedure OnCameraFrame(var Msg); message MM_FRAME_COMPLETE;
...
end;
procedure TMainForm.OnCameraFrame(var Msg);
begin
// it is alaways in updating state, only release this for a short moment
Display.Picture.Bitmap.EndUpdate();
Display.Picture.Bitmap.BeginUpdate();
// the camera thread is waiting, notify it that we are done.
RTLeventSetEvent(GuiHasFinishedEvent);
end;
This works like a charm.
--
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