OpenEuphoria

win32lib scrolling

• Posted by Derek Parnell <ddparnell at bigpond.com> Jul 11, 2003
• 576 views

A bug has been reported when trying to scroll trackbars or scroll bars that 
have a negative position value. It only shows up when you are scrolling 
with the mouse on the 'scrolling thumb'.

To fix it, in the win32lib routine called 'fDoScroll', find the lines ...

    elsif find(request, {SB_THUMBPOSITION, SB_THUMBTRACK}) then
        -- track thumb position
        pos = hi_word( wParam )

and add these lines immediately after the lines above.

        if pos > #7FFF then
            pos -= #10000
        end if

This should fix it.

You should also note that the documentation on w32HScroll is wrong. It 
should read ...

  parms = { integer position, integer ScrollType, integer WhichBar }

  'position' indicates the new value of a scrollbar or trackbar.

The stuff about the position being negative when the SB_ENDSCROLL action 
happens is no longer applicable.

-- 

cheers,
Derek Parnell