Vincent Snijders wrote: > I am confused, do you want to use the scrollbar for scrolling or the > mouse wheel? I want to use the scrollbar because it provides visual feedback about the location of the section of the visible data in a larger buffer of displayable data. I prefer that the scrollbar perform this function regardless of whether the mouse wheel is moved (with the mouse pointer hovering over the scrollbar) or the scrollbar handle is dragged with the mouse or the arrow or page up/down buttons are used. All methods should to the same thing; move the data display in response to scrollbar events. > If you want to use the mouse wheel, then use one of the OnMouseWheel* > events. I can see that this is possible (at the application level) but it complicates the software design to have to handle these independently of the scrollbar (events from which are the canonic source of movement control in this application). > If you want to use the scrollbar, use the events of the scrollbar, if > necessary. This is what I'd like to do but the problem is that the scale at which the scrollbar moves in response to mousewheel events does not seem to be under my control (via properties or events of TScrollBar) other than via some rough relationship to PageSize. I can't set PageSize arbitrarily (to control the mousewheel movement scaling) because it's also used to indicate how much of the available data is being displayed at the present time. > If you don't handle the mouse wheel events, then the LCL widgetset > interface or the underlying widget may translate the mousewheel to a > scroll message. This it indeed does (in GTK2 and Win32 at least). It's just not clear the mechanism by which the widget decides how far to move the scrollbar for each mousewheel event it translates.
Cheers, Bruce. -- _______________________________________________ Lazarus mailing list [email protected] http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
