LImageViewer::SetRequestedImage

#include "ltwrappr.h"

L_INT LImageViewer::SetRequestedImage(nCellIndex, pBitmaps, pBitmapIndexes, nLength, uFlags)

L_INT nCellIndex;	/* index of a cell */
pBITMAPHANDLE pBitmaps;	/* pointer to bitmaps array */
L_INT * pBitmapIndexes;	/* pointer to bitmap indexes array */
L_INT nLength;	/* length of the bitmap indexes array */
L_UINT uFlags;	/* reserved for future use */

Sends the requested images to the control; this function is used when the low memory usage feature is enabled (for more information see the LImageViewer::EnableCellLowMemoryUsage function).

Parameter	Description
nCellIndex	A zero-based index of the cell for which to pass the requested image.
pBitmaps	Array of a BITMAPHANDLE structure that contains the requested frames.
pBitmapIndexes	Array of Integers containing the index of each bitmap in pBitmaps in respective manner.
nLength	Length of the pBitmapIndexes array.
uFlags	Flag that indicate how to handle the images set. Possible values are:
	Value	Meaning
	CONTAINER_SETIMAGE_INSERT	[0x00000000] Insert the requested image. This is the default value.
	CONTAINER_SETIMAGE_REPLACE	[0x00000001] Replace the requested image with the corresponding index.

Returns

SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

The low memory usage feature works by stopping the control from loading all the frames at runtime. Instead, the control will load only the frames that are currently visible on the cell. The control will send a request each time the user scrolls down or up, changes the number of visible framesetc. For example, suppose the cell layout is a 2X2 (See LImageViewer::SetCellProperties), and the user needs to load more than 100000 frames. The control will not load them all. This function will send a callback (LImageViewer::LowMemoryUsageCallBack) when the cell is loaded requesting 4 frames (1, 2, 3 and 4) (because the cell is 2X2). Once the user scrolls down the cell to show frame number 5, frame number 1 will be disposed of because it is no longer visible, and the callback will be fired to request frame number 5. When frames are requested, the user is supposed to send them to the control using the LImageViewer::SetRequestedImage function.

For the callback, use the LImageViewer::LowMemoryUsageCallBack function, to use this callback, it must first be set by calling LImageViewer::EnableLowMemoryUsageCallBack function.

Required DLLs and Libraries

LTIVW

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Functions:	LImageViewer::Create, LImageViewer::Destroy, LImageViewer::InsertCell, LImageViewer::EnableLowMemoryUsageCallBack, LImageViewer::LowMemoryUsageCallBack, LImageViewer::SetCellBitmapList, Class Members
Topics:	Image Viewer Cells
	Image Viewer Functions: Image Viewer Cells