Standardized behavior of object selection in application UI

Question

This is more of a usability question. I want to know if there is any recommendation for selection behavior for an application development.

Example: there are objects in the UI you can select. You select 3 objects with holding down "CTRL". Then you release the "CTRL" button and left-click on one of marked objects. Should the other selected objects be unselected? I see this behavior in applications like Excel or any other app where you have "list-objects" you can select. Where does this behavior come from? Anyone knows if this is a standardized behavior? Thank you for your help.

Greetings.

Answer 1

Standards for selection of objects is as old as graphical interfaces (GUIs). Look at the style guides for Apple or Microsoft to see the definitions of selection and multiple selection.

You ask specifically about what should happen when multiple items are selected and a user clicks ("left-clicks") one of the objects. In all cases, that should reset the selection so that only the last-clicked item is selected -- because selection of an object always de-selects all other selected objects, if no multi-selection modifier is used. This is exactly what windows does if you select icons on the desktop, for example.