Deselect all for stockpiles?

I like to create stockpiles for a single resources, like wood or dirt. Every time I do, I have to manually deselect every category except for the one I want.

My process looks like this:

1. Click 'room'

2. Click '+' and drag out a new stockpile

3. Click on the 'Stockpile' job to bring up the Room production overlay

4. Scroll down to the 'Items' section, which has a list of all item categories

From there I can't find any way to deselect all, aside from manually unchecking every category. Am I missing something?