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How to Add List-View Image Lists

  • Artikkeli

This topic demonstrates how to add image lists to a list-view control.

You create only the image lists that the control uses. For example, if your application does not allow the user to switch to icon view, you do not need to create and assign a large icon list. If you create both large and small image lists, they must contain the same images in the same order, because a single value is used to identify a list-view item's icon in both image lists.

What you need to know

Technologies

Prerequisites

  • C/C++
  • Windows User Interface Programming

Instructions

To display item images, you must assign an image list to the list-view control. To do this, use the LVM_SETIMAGELIST message or the corresponding macro ListView_SetImageList, specifying whether the image list contains full-sized icons, small icons, or state images. To retrieve the handle to an image list that is currently assigned to a list-view control, use the LVM_GETIMAGELIST message. You can use the GetSystemMetrics function to determine appropriate dimensions for the full-sized and small icons.

In the following C++ code example, the application-defined function first creates image lists and then assigns them to a list-view control.

// InitListViewImageLists: Creates image lists for a list-view control.
// This function only creates image lists. It does not insert the items into
// the control, which is necessary for the control to be visible.   
//
// Returns TRUE if successful, or FALSE otherwise. 
//
// hWndListView: Handle to the list-view control. 
// global variable g_hInst: The handle to the module of either a 
// dynamic-link library (DLL) or executable (.exe) that contains
// the image to be loaded. If loading a standard or system
// icon, set g_hInst to NULL.
//
BOOL InitListViewImageLists(HWND hWndListView) 
{ 
    HICON hiconItem;     // Icon for list-view items.
    HIMAGELIST hLarge;   // Image list for icon view.
    HIMAGELIST hSmall;   // Image list for other views.

    // Create the full-sized icon image lists. 
    hLarge = ImageList_Create(GetSystemMetrics(SM_CXICON), 
                              GetSystemMetrics(SM_CYICON), 
                              ILC_MASK, 1, 1); 

    hSmall = ImageList_Create(GetSystemMetrics(SM_CXSMICON), 
                              GetSystemMetrics(SM_CYSMICON), 
                              ILC_MASK, 1, 1); 
    
    // Add an icon to each image list.  
    hiconItem = LoadIcon(g_hInst, MAKEINTRESOURCE(IDI_ITEM));

    ImageList_AddIcon(hLarge, hiconItem);
    ImageList_AddIcon(hSmall, hiconItem);

    DestroyIcon(hiconItem);
 
// When you are dealing with multiple icons, you can use the previous four lines of 
// code inside a loop. The following code shows such a loop. The 
// icons are defined in the application's header file as resources, which 
// are numbered consecutively starting with IDS_FIRSTICON. The number of 
// icons is defined in the header file as C_ICONS.
/*    
    for(index = 0; index < C_ICONS; index++)
    {
        hIconItem = LoadIcon (g_hinst, MAKEINTRESOURCE(IDS_FIRSTICON + index));
        ImageList_AddIcon(hSmall, hIconItem);
        ImageList_AddIcon(hLarge, hIconItem);
        Destroy(hIconItem);
    }
*/
    
    // Assign the image lists to the list-view control. 
    ListView_SetImageList(hWndListView, hLarge, LVSIL_NORMAL); 
    ListView_SetImageList(hWndListView, hSmall, LVSIL_SMALL); 
    
    return TRUE; 
}

List-View Control Reference

About List-View Controls

Using List-View Controls