how detect user indolence an comparison workbook

i wish take an movement an comparison workbook macro after generation indolence (hide/protect worksheets). best/simplest proceed grasp this?

'm presumption i'll application.ontime intermittently check user active. nonetheless events should i hoop user "active" (i.e. does something - anything - workbook)?

clarification: i wish detect all activity, only changes. i.e. including rodent clicks, selecting, copying, navigating keyboard, changing worksheets, ...

i'm presumption ui eventuality happens represents user activity, i set non-static thus:

lastactivitytime = now

and macro run application.ontime check non-static user active recently. events (other sheetchange) i need hoop set variable? i kind hoped there keyup mouseup events, twin substantially have enough.

update: i have implemented doing workbook_sheetactivate, workbook_sheetselectionchange workbook_windowactivate. practically substantially enough.