UI design - Include a Cancel button or not?

Question

We are designing the UI for a new line of business application. We have no real constraints and are free to design the UI as we see fit. The UI will be done in WPF and targeted for Windows 7, Vista, and XP Pro users.

Many dialog boxes contain OK and Cancel buttons in their lower right corner. Do you feel it is necessary to have this Cancel button or is the red X in the upper right corner sufficient? We are discussing this as we have been noticing more UIs that do not have cancel buttons, only the red X.

Answer 1

If you have that kind of freedom, consider eliminating dialog boxes from your application entirely, especially ones with the typical "OK | CANCEL" paradigm. Dialog boxes disrupt the flow of action and generally should only be used for things which absolutely require the program to interrupt the user.

You'll notice how disruptive they are in the web environment -- e.g., Stack Overflow only uses them when it needs to be able to OVERRIDE your action, e.g., when you navigate away from an unsubmitted answer.

Answer 2

From a user interface perspective, not including a cancel button might leave some users feeling like they have no choice, which is certainly not the case. Imagine the following simple decision scenario:

Warning: All of the files in the selected folder will be deleted. This action cannot be undone. Are you sure you would like to continue?

How silly would an interface be if the only option was Ok? Also, as noted above, on many platforms the Escape key is mapped to Cancel. It's also probably worthwhile setting a default button so that pressing the Enter/Space key doesn't inadvertently perform the action that cannot be undone.

Answer 3

+1 on including it. If you don't include it now and then need some different functionality on Cancel to Close later on, your users will already be used to automatically closing.

Answer 4

Include it!

Answer 5

Just like we have 'ESC' button on keyboard, we need 'Cancel' in dialogs.

A matter of usability :-)

Answer 6

Not only you should add it but also make sure ESC is mapped to it.