DISPCONTAINERBITMAPINFO

typedef struct tagDISPCONTAINERBITMAPINFO 
{ 
   L_UINT uStructSize; 
   L_UINT uWidth; 
   L_UINT uHeight; 
   L_UINT uXResolution; 
   L_UINT uYResolution; 
} 
DISPCONTAINERBITMAPINFO, * pDISPCONTAINERBITMAPINFO; 

The DISPCONTAINERBITMAPINFO structure provides information about the images that are going to be set through the LImageViewerCell::SetRequestedImage function when the low memory usage feature is enabled. This feature is available in version 16 or higher.

Members

uStructSize

Size of this structure in bytes, for versioning. Use the sizeof() operator to calculate this value.

uWidth

Value that represents the width of the bitmap, in pixels.

uHeight

Value that represents the height of the bitmap, in pixels.

uXResolution

Value that represents horizontal resolution, in dots per inch. Some file formats save this value in the file header.

uYResolution

Value that represents vertical resolution, in dots per inch. Some file formats save this value in the file header.

Comments

This structure was created especially to provide the information that needs to be set prior to enabling the low memory usage feature.

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 LImageViewerCell::SetCellProperties), and the user needs to load more than 100000 frames. The control will not load them all. This function will send a callback (LImageViewerCell::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 function LImageViewerCell::SetRequestedImage.

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

This structure is used with the following functions:

LImageViewerCell::EnableLowMemoryUsageCallBack