How to create custom onscreen keyboards?

Im about to start creating a custom onscreen keyboard for my WP7 app. An out of the box SIP will not work since they can't be customized or built from scratch with .NET.

Ideally the keyboard would activate like a SIP. Specifically, appear when the textbox receives focus. Docking to the bottom of the screen would be nice, too.开发者_开发问答

Any ideas where I could find samples of this?

Also, do you have any recommendations or lessons learned you could share?

I think you'll be making this sample ;)

The challenge with letting textbox take focus is likely going to be the built in SIP is going to appear. ReadOnly is an option, but you'll either lose or need to find a way to retain/mimic the cursor if that visual queue is important to you.