I hope I am not the only person who did not know this (apologies if that is the case).
A few weeks ago while at an event in Finland, my emulator did not detect an orientation change during a demo. Some one suggested I restart the emulator, I did, and it worked (against my instinct). Today, I found out what’s going on.
When you use the Page Up/Page down button, the emulator let’s you toggle the Software Input Panel (SIP) on and off. Also when you use the Pause/Break button the emulator disables the SIP and let’s you enter text via your keyboard. All that works neatly as expected. I use that all the time. The part I did not know is that the emulator does not support orientation changes when the keyboard is enabled. This is all well documented in the keyboard mapping page: http://msdn.microsoft.com/en-us/library/ff754352(v=VS.92).aspx but I did not know.
Not sure if it has always been documented and I missed it or it is new; either way, fooled me once.. but not again..
Happy Windows Phone coding (and don’t forget to read the manual now and then !!)