How should I include a multiple selection mechanism in a checklist site?

Question

I'm building a small checklist on a website. It'll have multiple items that are able to be "completed" by checking them off the list by ticking a checkbox. However, I also want to add a multi-select feature that a user can select multiple to delete (or a similar action).

Almost all sites have a checkbox reserved for selecting multiple items: look at any email program. The only problem with using that approach is using the checkbox to mark a task as "completed" only seems natural. Wouldn't two different columns of checkboxes be confusing to a user? I've been thinking about a "shift-click" type thing, but that'd be impossible to do on mobile. How should I accomplish this?

Answer 1

At first, please make yourself sure that such a feature is necessary — you describe you checklist as "small", so multiple selection can make your tiny checklist more functional, more complex, but it can be not useful for and unused by most users (so by adding such a feature in certain contexts cane make the checklist worse, not better).

If such a feature is necessary, you may use the approach, that there is checkbox to mark task done by clicking on it (it is better to make it more accented, custom — not using standard webform design). But clicking/touching on other area of checklist makes it state "selected" (to indicate it, you can change the whole background of item).

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