Re: [PATCH resend] comctl32: When adding a scrollbar to a listview, update the other one.

[Alistair Leslie-Hughes]

Hi Alex,

On 03/05/17 14:53, Alex Henrie wrote:
> Cc: Nikolay Sivov <nsivov(a)codeweavers.com>
> +static void LISTVIEW_UpdateScroll(LISTVIEW_INFO *infoPtr)
> +{
> +    INT dx, dy;
> +
> +    if ((infoPtr->dwStyle & LVS_NOSCROLL) || !is_redrawing(infoPtr)) return;
> +
> +    /* Setting the horizontal scroll can change the listview size
> +     * (and potentially everything else) so we need to recompute
> +     * everything again for the vertical scroll and vice-versa
> +     */
> +
> +    dx = LISTVIEW_UpdateHScroll(infoPtr);
> +    dy = LISTVIEW_UpdateVScroll(infoPtr);
> +    dx += LISTVIEW_UpdateHScroll(infoPtr);
> +    dy += LISTVIEW_UpdateVScroll(infoPtr);
> +
> Is there any reason your calling update twice for each control?

Best Regards
 Alistair Leslie-Hughes

[PATCH resend] comctl32: When adding a scrollbar to a listview, update the other one.

[Alex Henrie]

2017-05-02 23:10 GMT-06:00 Alistair Leslie-Hughes <leslie_alistair(a)hotmail.com>:
> Hi Alex,
>
> On 03/05/17 14:53, Alex Henrie wrote:
> > Cc: Nikolay Sivov <nsivov(a)codeweavers.com>
> > +static void LISTVIEW_UpdateScroll(LISTVIEW_INFO *infoPtr)
> > +{
> > +    INT dx, dy;
> > +
> > +    if ((infoPtr->dwStyle & LVS_NOSCROLL) || !is_redrawing(infoPtr)) return;
> > +
> > +    /* Setting the horizontal scroll can change the listview size
> > +     * (and potentially everything else) so we need to recompute
> > +     * everything again for the vertical scroll and vice-versa
> > +     */
> > +
> > +    dx = LISTVIEW_UpdateHScroll(infoPtr);
> > +    dy = LISTVIEW_UpdateVScroll(infoPtr);
> > +    dx += LISTVIEW_UpdateHScroll(infoPtr);
> > +    dy += LISTVIEW_UpdateVScroll(infoPtr);
> > +
> > Is there any reason your calling update twice for each control?

For example:

1. Because of new content, a horizontal scrollbar is added, taking up
some of the vertical space (dx = LISTVIEW_UpdateHScroll(infoPtr))
2. Because there is not enough vertical space now, a vertical
scrollbar is added, taking up some of the horizontal space (dy =
LISTVIEW_UpdateVScroll(infoPtr))
3. The horizontal scrollbar thumb's position is updated to reflect
that there is less horizontal space now (dx +=
LISTVIEW_UpdateHScroll(infoPtr))

Or:

1. Because of new content, a vertical scrollbar is added, taking up
some of the horizontal space (dy = LISTVIEW_UpdateVScroll(infoPtr))
2. Because there is not enough horizontal space now, a horizontal
scrollbar is added, taking up some of the vertical space (dx +=
LISTVIEW_UpdateHScroll(infoPtr))
3. The vertical scrollbar thumb's position is updated to reflect that
there is less vertical space now (dy +=
LISTVIEW_UpdateVScroll(infoPtr))

-Alex