Futurebasic/Language/Reference/scroll
SCROLL
[edit | edit source]Syntax
[edit | edit source]SCROLL (h1,v1)-(h2,v2),hPixels%,vPixels%
Description
[edit | edit source]This statement scrolls the pixels in the rectangle (h1,v1)-(h2,v2), by a horizontal distance of hPixels% and a vertical distance of vPixels%, in the current output window. Positive values of hPixels% scroll to the right; positive values of vPixels% scroll downward; use negative values to scroll in the opposite direction(s). SCROLL is often used in conjunction with scroll bars to view a graphic that is too large to fit entirely in the window.
SCROLL generates a _wndRefresh event, which your program can detect in its dialog-event handling routine the next time a HANDLEEVENTS statement is executed. Your dialog-event handling routine should respond to this event by redrawing the portion of the window that was left blank by the scroll. If you don't redraw this area explicitly, it will be filled with the window's current background color and pattern.
FB Lite behavior:
When you use the "FB Lite" runtime, SCROLL operates only on the Graphics Window. Because "FB Lite" refreshes the window automatically, you won't receive a _wndRefresh event.
See Also
[edit | edit source]SCROLL BUTTON; ON DIALOG