Due to accessibility issues, I would like to install a tub spout with a handheld shower outlet. I know that when the diverter knob is pulled, water will be directed to the handheld outlet. If I also install a shutoff valve on the handheld, will the regular shower head I currently have then work?

If you Google "3 way shower diverter", you can find a number of them. Sprite, Delta etc.

Thanks ma064, but I'm looking for control at the tub spout level as the shower head is too difficult to reach.