Limiting ListView's multi-selection

Unity Engine
,
1

Is it possible to customize the multi-selection behavior of ListView in any way? For example, I’d like to allow for continuous ranges of items to be selected, but not individual disjoint items (i.e. the built-in Shift+Click behavior, but disallow the built-in Ctrl/Cmd+Click behavior).

All the methods controlling this behavior in BaseCollectionView are non-virtual and private, so overriding it seems difficult.

As a partial solution I’ve added my own handlers for PointerDown and PointerUp in a derived class to prevent the handlers in BaseCollectionView from receiving them:

RegisterCallback<PointerDownEvent>((evt) =>
{
    if (evt.actionKey)
    {
        evt.StopImmediatePropagation();
    }
});
RegisterCallback<PointerUpEvent>((evt) =>
{
    if (evt.actionKey)
    {
        evt.StopImmediatePropagation();
    }
});

This effectively removes all Ctrl+Click behavior, but it would be a little nicer if Ctrl+Click could still be used to select or deselect items at either end of the current selected range or to single-select items. Is there a good way to allow this without allowing disjoint selections?

2

Hey. Currently, there is no way to customize the multi-selection. Something you could do is in your pointer callbacks check if the element you are clicking is an element next to a selected element. You could get the elements that can be added in the selection using BaseVerticalCollectionView.GetRootElementForIndex and see if it matches the clicked item.