TScrollMetro

Source: source/classes/scrollm.prg

Inherits from: TControl

TScrollMetro provides a modern Metro-style scrollbar control. It replaces the classic Windows scrollbar with a flat, touch-friendly design suitable for tablet and modern UI applications. The control supports programmatic positioning, range management, and code-block event hooks for all scroll actions.

Key DATA Members

DATA	Type	Description
`lVertical`	Logical	Orientation: `.T.` for vertical, `.F.` for horizontal
`nMin / nMax`	Numeric	Scroll range minimum and maximum values
`nPgStep`	Numeric	Page step increment for page-up/page-down actions
`nPos`	Numeric	Current scroll thumb position
`bGoUp / bGoDown`	Code block	Executed when the up/left or down/right button is clicked
`bGoTop / bGoBottom`	Code block	Executed when the thumb is dragged to the top or bottom
`bPageUp / bPageDown`	Code block	Executed on page-up/page-down track area click
`bPos / bTrack`	Code block	Executed on position change and thumb tracking

Methods

Method	Description
`New( nRow, nCol, nMin, nMax, nPgStep, lVert, oWnd, nW, nH )`	Create a new Metro scrollbar with range, step, and orientation
`SetRange()`	Update the scroll range from `nMin` and `nMax` values
`SetPos( nPos ) / GetPos()`	Set or retrieve the current scroll thumb position
`GoUp() / GoDown()`	Move the thumb up (or left) / down (or right) by one step
`GoTop() / GoBottom()`	Move the thumb to the minimum or maximum position
`PageUp() / PageDown()`	Move the thumb by the page step amount

Example: Vertical Scrollbar for Browse

#include "FiveWin.ch"

function Main()

   local oWnd, oScroll
   local nPos := 0

   DEFINE WINDOW oWnd TITLE "TScrollMetro Demo" SIZE 400, 300

   oScroll := TScrollMetro():New( 10, 370, 0, 100, 10, .T., oWnd, 20, 250 )

   oScroll:bGoUp    := { || nPos := oScroll:GetPos(), oWnd:Refresh() }
   oScroll:bGoDown  := { || nPos := oScroll:GetPos(), oWnd:Refresh() }
   oScroll:bPageUp  := { || nPos := oScroll:GetPos(), oWnd:Refresh() }
   oScroll:bPageDown:= { || nPos := oScroll:GetPos(), oWnd:Refresh() }

   ACTIVATE WINDOW oWnd CENTERED

return nil

Notes

The control fires code-block events for each scroll action: bGoUp, bGoDown, bGoTop, bGoBottom, bPageUp, bPageDown, bPos, and bTrack.
Orientation is set at creation time via the lVert parameter and cannot be changed dynamically.
Use SetRange() after changing nMin or nMax to recalibrate the scroll thumb.
The Metro scrollbar is particularly suited for touch-screen applications where the narrow track of classic scrollbars is difficult to interact with.

TScrollMetro

Key DATA Members

Methods

Example: Vertical Scrollbar for Browse

Notes

See Also