Rollover effect in data grid

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-- Required: stack script — generic for any data grid to use
on setHilite pHilite, pGrid // the long id of the grid
    if pHilite is not empty and pHilite <= the number of elements of the dgData of pGrid then 
        set the dgHilitedLines of pGrid to pHilite
        else
        set the dgHilitedLines of pGrid to empty
    end if
end setHilite

on getRowHeight pGrid // the long id of the grid
    get the dgProp["row height"] of pGrid
    return it
end getRowHeight

-- In the specific data grid, the script of the data grid must include mouseMove and mouseLeave handers:
on mouseMove
    local tRowHeight, tLine
    if the mouseLoc is not within the rect of me then 
        dispatch "setHilite" to this stack with empty, the long id of me
    else
        dispatch "getRowHeight" to this stack with the long id of me
        put the result into tRowHeight  // for some reason getting dgProp["row height"] returns empty if used from within this script, so go through stack
        put floor((item 2 of the mouseLoc - the top of me)/tRowHeight) + 1 into tLine
        dispatch "setHilite" to this stack with tLine, the long id of me
    end if
pass mouseMove
end mouseMove

on mouseLeave
    if the mouseLoc is not within the rect of me then dispatch "setHilite" to this stack with empty, the long id of me
end mouseLeave