TScrollImg

Source: source/classes/scrolimg.prg

Inherits from: TPanel

TScrollImg is an image banner / carousel control that displays a scrolling collection of images. It supports multiple display modes, automatic animation, fading transitions, zoom on hover, click actions per image, and state persistence. Originally designed for product showcases and advertisement banners.

Key DATA Members

DATA	Type	Description
`aElements`	Array	Array of element definitions (file, URL, action, prompt)
`nImages`	Numeric	Number of images loaded from the banner list
`nMode`	Numeric	Display mode 1-4 (scroll direction / layout variant)
`nSpeed`	Numeric	Scroll speed in pixels per timer tick
`lRunning`	Logical	Animation is currently running
`lPaused`	Logical	Animation is paused
`aOpacity`	Array	Per-image opacity values (0-255)
`nZoomedImage`	Numeric	Index of the currently zoomed image (0 = none)
`lFading`	Logical	Fading transition is in progress
`lMouseWheel`	Logical	Enable mouse wheel scrolling
`lChangeSpeed`	Logical	Allow speed change via +/- keys

Methods

Method	Description
`New( nRow, nCol, nW, nH, oWnd, aBanners, nMode, nSpeed, ... )`	Create a new image carousel with banner file list and display mode
`Redefine( nId, oWnd, aBanners, nMode, nSpeed, ... )`	Redefine from a dialog resource
`Reset()`	Reset the carousel to its initial state, reposition all images
`Animate()`	Start or restart the scrolling animation timer
`Paint()`	Render the background and all visible images
`TimerAction()`	Timer callback that advances the scroll position each tick
`SaveState( cFile )`	Save the current carousel state (positions, images) to a file
`LoadState( cFile )`	Restore a previously saved carousel state from a file
`MouseMove( nRow, nCol )`	Handle mouse movement for hover detection and zoom
`LButtonUp( nRow, nCol )`	Execute action associated with the clicked image
`KeyDown( nKey, nFlags )`	Handle +/- keys for speed control
`MouseWheel( nKeys, nDelta, nX, nY )`	Handle mouse wheel for manual scrolling

Example: Image Carousel

#include "FiveWin.ch"

function Main()

   local oWnd, oScroll

   DEFINE WINDOW oWnd TITLE "Image Carousel" SIZE 800, 300

   oScroll = TScrollImg():New( 10, 10, 780, 240, oWnd,;
      { "banner1.jpg", "banner2.jpg", "banner3.jpg", "banner4.jpg" },;
      1, 3, 20 )

   oScroll:Animate()

   ACTIVATE WINDOW oWnd CENTERED

return nil

Notes

The aBanners array can contain filenames, or sub-arrays with { file, url, action, prompt } for extended interactivity.
Mode determines the scroll direction: 1 = horizontal left, 2 = horizontal right, 3 = vertical up, 4 = vertical down.
When the mouse hovers over an image, nZoomedImage enables a zoom effect using nZoomFactor.
Opacity transitions (fading) are applied via aOpacity and lFading / nFadeDuration.
State persistence with SaveState / LoadState allows the carousel to resume from where it left off.

TScrollImg

Key DATA Members

Methods

Example: Image Carousel

Notes

See Also