Thread: Need help With Scrolling Text - Wanna make Dialog Credits...

Hi mates,

jep, this is my 1° post here... great resource.

I've try to find some pure api (NO MFC) example for simple
scrolling text in my own dialog credits... i want compile it
with LCC, then i need it in pure api.

I've only found mfc source example but none in pure api.

I need to scroll text into a small dialog about box...
someting like this:
http://www.codeproject.com/bitmap/scrollingcredits.asp

Please if someone can help me...
very appreciated

TNX

The easy solution that isn't as fancy as the link you provided is just use an edit box. You can make the edit box disabled and without a border and it will "blend in" with the rest of the dialog (if that's desired). All you have to do then is populate the edit box (WM_SETTEXT) and scroll the edit box (EM_LINESCROLL) on a timer.

The fancy solution will require some basic GDI know-how. For flicker-free smooth scrolling, you'll want to use a memory DC that gets bit-blitted to the paint DC.
This article should cover the neccessary know-how for the facny solution.

gg

Tnx mate

If i use an EditBox (EDITTEXT ?) i must use EM_LINESCROLL ...
the it scroll 1 LINE. but if i want scroll 1 or 2 pixel ?

Lemme see your link...

If you want pixel by pixel scrolling, then you'll have to use GDI solution.

gg

oki... i'll try to do...

Here's something to start with. Usage code in attached zip. Flicker, etc are left up to you to deal with as described in link by Codeplug.

Code:

static LRESULT CALLBACK ScrollerProc (HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	switch (uMsg)
	{

		case WM_CREATE:
			return 0;

		case WM_DESTROY:
			return 0;

		case WM_VSCROLL:
			SetWindowLong(hwnd, 0, wParam);   /* Save scroll position provided in wParam */
			InvalidateRect(hwnd, NULL, TRUE);

		case WM_PAINT:
		{
			PAINTSTRUCT ps;
			RECT rc;
			TCHAR szWndText[8192];

			GetClientRect(hwnd, &rc);
			rc.top -= GetWindowLong(hwnd, 0);  /* Move top of text up by scroll position */

			GetWindowText(hwnd, szWndText, 8192);

			BeginPaint(hwnd, &ps);

				DrawText(ps.hdc, szWndText, lstrlen(szWndText), &rc, DT_CENTER);

			EndPaint(hwnd, &ps);

			return 0;
		}
	}

	return DefWindowProc(hwnd, uMsg, wParam, lParam);
}


BOOL ScrollerRegister(void)
{
	WNDCLASSEX wc = { 0 };

	wc.cbSize        = sizeof (WNDCLASSEX);
	wc.style         = CS_OWNDC | CS_HREDRAW | CS_VREDRAW;
	wc.cbClsExtra    = 0;
	wc.cbWndExtra    = sizeof(LONG); /* Room to save scroll position */
	wc.hInstance     = GetModuleHandle(NULL);
	wc.lpfnWndProc   = ScrollerProc;
	wc.hIcon         = NULL;
	wc.hCursor       = LoadCursor(NULL, IDC_ARROW);
	wc.hbrBackground = (HBRUSH) (COLOR_WINDOW + 1);
	wc.lpszMenuName  = NULL;
	wc.lpszClassName = SCROLLER_CLASS;
	wc.hIconSm       = NULL;

	return RegisterClassEx(&wc);
}


BOOL ScrollerUnregister(void)
{
	return UnregisterClass(SCROLLER_CLASS, GetModuleHandle(NULL));
}

TNX mates

Now i've understand exactly how to... isn't same as moving layers... i must draw & formatting the text every time i move it...

oki...

You should be able to create and render the text in one large off screen DC. Then the scrolling is achieved by bit-blit'ing a "window" of the off screen DC.

gg

Maybe you could put the text in a static control and just move it up on the timer interval.

Originally posted by anonytmouse
Maybe you could put the text in a static control and just move it up on the timer interval.

this is another good idea...