Most usable select all/deselect all checkbox format

Question

What is the best pattern for having a select all or deselect all checkboxes. Can someone come up with a better way to have it in this form:

Answer 1

I'll be honest, I've never liked the idea of using a checkbox for the "select all" option, even though you see it a lot. It's not a single item to be picked, it's an action. And if you select all and then start unselecting individual items in the list, the "checked" state of the select all checkbox becomes inherently confusing. I prefer to use a simple but obvious link/button that toggles between "select all" and "unselect all" as it is clicked. There is no state to confuse you with when individual items have been deselected, and the outcome of pushing the button is never in doubt. The exclusive nature of the operation makes it perfectly reasonable to toggle back and forth (rather than using two always visible buttons; one for select all, one for unselect all), since you are at most two clicks away from your desired behavior. And it visually separates out this "action" from the individual items, preventing misclicks and distinguishing behavior.

Answer 2

If you can format your dialog with lists, I like the "checkbox in the list header" method (and most users intutively know how to use it).

If you do not want to use a list, I think a button or a hyperlink (that toggles from "Select All" to "Select None" would work better than yet another checkbox which is hard to make out among all the other checkboxes. Also, unchecking a "check all" checkbox would not necessarily immply a "check none" functionality for a user.