Multi select cascading dropdown in Power Apps

 

Left(Concat(ColDivisionSelectedValues, Title & ";"),Len(Concat(ColDivisionSelectedValues, Title & ";")) -1)

Plus icon

Set(_popup,true);

Set(DivisionGalleryViewing,true);

Set(DropdownName,"Division");

Gallery Division:

SortByColumns(ColDivisionDropdown, "Title")

Check box OnCheck: Collect(ColDivisionSelectedValues, ThisItem)

OnUnCheck: Remove(ColDivisionSelectedValues,ThisItem);

Remove(

    ColDistrictSelectedValues,

    Filter(

        ColDistrictSelectedValues,

        Division.Value = ChkBoxDivision_1.Text

    )

);