How to avoid opening a dialog from within a dialog?

Question

I'm designing a mobile modal dialog which will prompt users to activate a critical app feature related to the security of their data. The dialog should include two action:

1. ACTIVATE (for activating the feature)
2. DON'T SHOW AGAIN (self explanatory)

If users will choose 'DON'T SHOW AGAIN', I'd like to add a short comment that would explain how the feature could be activated in the future. Obviously, I'd like to avoid opening another dialog for the purpose of displaying that comment. One straight-forward solution is to add a 'DON'T SHOW AGAIN' checkbox to the body of the dialog, which when checked, will display a comment underneath the checkbox with instructions for activating the feature. In this case, the modal dialog actions will be:

1. ACTIVATE
2. CANCEL

What are your thoughts about such solution? Is it a good practice to have a checkbox within a modal dialog?

(Screenshot of a relatively similar use case attached for reference).

Answer 1

I would opt for your second option, as it is a clear Yes/No (Activate/Cancel) option. I don't think that the 'Don't show me again' option is as clear as you might expect to the user if they are only faced with that and 'Activate'.

Go for the layout that uses a checkbox and then expands to reveal how to turn that back on again.

It's a typical convention, and I wouldn't worry about disabling the option to 'Activate', even if by activating they won't be shown the message again anyway. This follows expected behaviour, and avoids confusion as often the 'Don't show me again' relates to both options.