[Lazarus] Mouse wheel scroll bar increment size?

[Martin Friebe]

You can catch the scroll message in your application, and determine the 
action (and the scale) yourself.

Have a look at SynEdit:
    procedure WMVScroll(var Msg: {$IFDEF 
SYN_LAZARUS}TLMScroll{$ELSE}TWMScroll{$ENDIF}); message WM_VSCROLL;


Best Regards
Martin


Bruce Tulloch wrote:
> Interesting thread but I may have not asked the right question...
>
> I'm trying to understand the scaling of the mousewheel as it affects the
> TScrollbar control specifically. Not for scrolling in SynEdit or case of
> scrolling text or similar purposes in a generic desktop application.
>
> Instead I'm looking at using it to scroll other types of data
> (waveforms, images etc) on screen using a TScrollBar as the controlling
> widget where the scale at which the data moves definitely wants to be
> under application (not O/S or desktop preferences) control.
>
> Am I to understand that this is currently outside the scope of LCL? IOW,
> is mousewheel scaling O/S defined and the application just has to accept
> the resolution of what it's been given on each platform?
>
> TScrollBar defines LargeSize and SmallSize properties to specify how
> much to move when the Page Up/Down keys and arrow keys (among other
> things) are pressed. What I'm interested in is a similar mechanism to
> specify the resolution for mousewheel events instead of having them tied
> in some rubbery platform dependent way to the current
> TScrollBar.PageSize setting.
>
> Does (or can) such a thing exist?
>
> If not, then the Mac solution (with an application configurability
> option) certainly seems to be the best compromise.
>
> Cheers, Bruce.
>   
>