IG_dspl_scroll

This function is designed to handle scrollbar messages from an hWnd window.

Declaration:

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AT_ERRCOUNT ACCUAPI IG_dspl_scroll_handle( [IN] HIGEAR hIGear, [IN] DWORD dwGrpID, [IN] HWND hWnd, [IN] AT_MODE nScrlType, [IN] AT_MODE nScrlMode, [IN] LONG lScrlValue, [OUT] LPAT_SCROLL_INFO lpScrollInfo );

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AT_ERRCOUNT   ACCUAPI  IG_dspl_scroll_handle( 
        [IN] HIGEAR hIGear, 
        [IN] DWORD dwGrpID,
        [IN] HWND hWnd, 
        [IN] AT_MODE nScrlType,
        [IN] AT_MODE nScrlMode,
        [IN] LONG lScrlValue,
        [OUT] LPAT_SCROLL_INFO lpScrollInfo
);

Arguments:

Name	Type	Description
hIGear	HIGEAR	ImageGear handle of image.
dwGrpID	DWORD	Identifier of group that will be used to perform operation.
hWnd	HWND	Handle of window where image is displayed and where scrolling is performed.
nScrlType	AT_MODE	Scroll command. Its value is platform dependent. For Win32 platforms there should be LOWORD(wParam) and for Win16, wParam. Valid values are: IG_DSPL_SCROLL_HORIZONTAL IG_DSPL_SCROLL_VERTICAL
nScrlMode	AT_MODE	Scroll command. Its value is platform dependent. For Win32 platforms there should be LOWORD(wParam) and for Win16, wParam. Valid values are: IG_DSPL_HSCROLLBAR IG_DSPL_HSCROLLBAR_AUTO IG_DSPL_HSCROLLBAR_ENABLE IG_DSPL_HSCROLLBAR_DISABLE IG_DSPL_VSCROLLBAR IG_DSPL_VSCROLLBAR_AUTO IG_DSPL_VSCROLLBAR_ENABLE IG_DSPL_VSCROLLBAR_DISABLE
nScrlValue	LONG	Scroll value. It is also platform dependent and its value may have a different meaning from nScrlType. Under the Windows platform, it is not used because the scroll position is obtained directly from the scrollbars.
lpScrollInfo	LPAT_SCROLL_INFO	Receive updated scroll parameters (not scrollbar). If NULL then it is ignored.

Return Value:

Returns the number of ImageGear errors that occurred during this function call.

Supported Raster Image Formats:

All pixel formats supported by ImageGear for C and C++.

Example:

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HIGEAR hIGear; /* HIGEAR handle of image / DWORD nGrpID; / display group identifier / ... case WM_HSCROLL: / horizontal scrolling / IG_dspl_scroll_handle( hIGear, nGrpID, hWnd, IG_DSPL_SCROLL_HORIZONTAL, LOWORD(wParam), HIWORD(wParam), NULL ); break; case WM_VSCROLL: / vertical scrolling */ IG_dspl_scroll_handle( hIGear, nGrpID, hWnd, IG_DSPL_SCROLL_VERTICAL, LOWORD(wParam), HIWORD(wParam), NULL ); break; ...

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HIGEAR           hIGear;       /* HIGEAR handle of image      */ 
DWORD           nGrpID;       /* display group identifier     */
 ...
case WM_HSCROLL:           /* horizontal scrolling   */
IG_dspl_scroll_handle( hIGear, nGrpID, hWnd, IG_DSPL_SCROLL_HORIZONTAL, LOWORD(wParam),
HIWORD(wParam), NULL );
        break;
case WM_VSCROLL: /* vertical scrolling */
IG_dspl_scroll_handle( hIGear, nGrpID, hWnd, IG_DSPL_SCROLL_VERTICAL, LOWORD(wParam),
HIWORD(wParam), NULL );
        break;
 ...

Remarks:

This function should not be used to set the absolute scroll position; function IG_dspl_scroll_to() should be used instead.