"jonfroehlich" <jonfroehl...@gmail.com> wrote in message

> The Microsoft.WindowsMobile.Status.SystemState class offers a great
> way to track a number of interesting and useful device system states
> (e.g., incoming phone calls, battery strength, etc.). However,
> recently I observed that the SystemState.Changed += new
> ChangeEventHandler(OnSystemStateChanged) subscription must be made
> from the UI thread. Has anyone else run into this? I attempted to
> write a console app that uses many of these system state
> notifications; however, none of the events were actually occurring.
> Once I switched to a form-based application, everything worked great.

> Is this documented somehwere? If so, I couldn't find it. I am
> programming in .NET CF 2 for Windows Mobile 5.0 devices.

> http://msdn2.microsoft.com/en-us/library/microsoft.windowsmobile.stat...

> Most of those events come from windows messages being posted at a low level
> (FileSystemWatcher works int he same way too).  If you never call
> Application.Run, no message pump is ever created, so no windows messages are
> ever dispatched.

> I don't think I've ever seen it documented, but if you walk through the
> aygshell source code in Platform Builder (which a lot of these come from
> eventually), you'll see that's how they work.  I agree that it's a poor
> choice, but it's how it was implemented.  The workaround is a very long,
> tedious process (again, we've done it for file system notifications)  of
> reimplementing the entire listening system, creating a hidden window for
> your app or implementing a Run() that doesn't take a Form (like we did in
> the SDF).

> --

> Chris Tacke, eMVP
> Join the Embedded Developer Communityhttp://community.opennetcf.com

> "jonfroehlich" <jonfroehl...@gmail.com> wrote in message

> news:1193422785.905979.317920@v29g2000prd.googlegroups.com...

> > The Microsoft.WindowsMobile.Status.SystemState class offers a great
> > way to track a number of interesting and useful device system states
> > (e.g., incoming phone calls, battery strength, etc.). However,
> > recently I observed that the SystemState.Changed += new
> > ChangeEventHandler(OnSystemStateChanged) subscription must be made
> > from the UI thread. Has anyone else run into this? I attempted to
> > write a console app that uses many of these system state
> > notifications; however, none of the events were actually occurring.
> > Once I switched to a form-based application, everything worked great.

> > Is this documented somehwere? If so, I couldn't find it. I am
> > programming in .NET CF 2 for Windows Mobile 5.0 devices.

> >http://msdn2.microsoft.com/en-us/library/microsoft.windowsmobile.stat...