Silverlight printing busy\progress bar.

Question

I'm using Silverlight 4 to print but I would like some sort of progress bar or busy indicator.

I've tried to using a progress bar but it is not really working. The 2 issues I have are:

• the progress bar does not indicate progress, I have IsIndeterminate=True, but it does not animate when printing starts (Print dialog's Print button is clicked)
• the progress bar visibility is not being set at the proper time, depending upon where I put the code to set visibility it displays either too soon (before print is clicked) or too late (after printing has worked for awhile)

I'm guessing, but I think the reason for the above is because when the print dialog is displayed Silverlight has handed off control to the OS for prining(??).

I tried using a dispatcher invoke but I get a security exception (dialog can only be displayed from user click).

Any ideas on how to deal with either of the above issues?

thanks.