Question

Could anyone could point me to some code/give me ideas on how to create a smooth scrolling vertical marquee for VFP 8 or 9?

Any help is appreciated.

Was it helpful?

Solution

Here's a quick program that will scroll messages. Put the following in a prg file and run it.

I'd make a containerScrollArea a class that encapsulates the timer, labels, and scrolling code. Give it GetNextMessage method that you can override to retrieve the messages.

* Put a container on the screen to hold our scroller
_screen.AddObject("containerScrollArea", "container")

WITH _Screen.containerScrollArea
    * Size it
    .Visible = .t.
    .Width = 100
    .Height = 100

    * Add two labels, one to hold each scrolling message
    .AddObject("labelScroll1", "Label") 
    .AddObject("labelScroll2", "Label") 

    * This timer will move the labels to scroll them
    .AddObject("timerScroller", "ScrollTimer")
ENDWITH

WITH _Screen.containerScrollArea.labelScroll1
    * The labels are positioned below the margin of the container, so they're not initially visible
    .Top = 101
    .Height = 100
    .Visible = .t.
    .WordWrap = .t.
    .BackStyle= 0
    .Caption = "This is the first scrolling text, which is scrolling."
ENDWITH

WITH _Screen.containerScrollArea.labelScroll2
    * The labels are positioned below the margin of the container, so they're not initially visible
    .Top = 200
    .Height = 100
    .Visible = .t.
    .WordWrap = .t.
    .BackStyle= 0
    .Caption = "This is the second scrolling text, which is scrolling."
ENDWITH

* Start the timer, which scrolls the labels
_Screen.containerScrollArea.timerScroller.Interval = 100


DEFINE CLASS ScrollTimer AS Timer
    PROCEDURE Timer

        * If the first label is still in view, move it by one pixel
        IF This.Parent.labelScroll1.Top > -100
            This.Parent.labelScroll1.Top = This.Parent.labelScroll1.Top - 1
        ELSE
            * If the first label has scrolled out of view on the top of the container, move it back to the bottom.
            This.Parent.labelScroll1.Top = 101
            * Load some new text here
        ENDIF

        IF This.Parent.labelScroll2.Top > -100
            * If the second label is still in view, move it by one pixel
            This.Parent.labelScroll2.Top = This.Parent.labelScroll2.Top - 1
        ELSE
            * If the second label has scrolled out of view on the top of the container, move it back to the bottom.
            This.Parent.labelScroll2.Top = 101
            * Load some new text here
        ENDIF
    ENDPROC
ENDDEFINE

OTHER TIPS

You can use Scrollable Container

Unfortunately the nature of my work leaves me no time for fooling around with graphics, however if I did I would look into using GDI+ with VFP. Here is an article to get you started

Licensed under: CC-BY-SA with attribution
Not affiliated with StackOverflow
scroll top