Advanced MFC Programming

Chapter 14. Views
}
ff.Close();
If we execute the sample, we need to wait for a while before the procedure of building directory tree is
completed. This waiting time is especially long for a system containing many drives and directories. This is
why we only add fist and second level directories to the tree view window at the beginning. If we build the
whole directory map before bringing up the window, the user will experience a very long waiting time. We
will add new nodes to the tree only when a node is expanded and its sub-level contents need to be revealed.
14.6 Simple Explorer, Step 4: Displaying Files
In the sample, all files will be listed in the list view that is located at the right pane of the client splitter
window. Like what is implemented in class CDirView, we need to enumerate files under a directory and add
corresponding nodes to the list control in order to display the files.
The list view window will display all the directories and files contained in the selected directory. If the
currently selected directory changes, we must destroy the list view and create a new one. For this purpose,
in the sample, a new function CExplorerView::ChangeDir() is implemented, which can be used to create
the list view from the currently selected directory.
Image Lists
Before adding any file to the list view, we need to prepare image lists. This procedure is almost the
same with that of tree view. The only difference between the two is that for list view we have more choices.
This is because the items contained in a list view can be displayed in different styles, and for each style we
can use a different type of images.
A list view can display items in one of the four styles: big icon (default style), small icon, list, report.
We can prepare two image lists, one for big icon style, one for other three styles.
We can display different file types using different icons, this is how the files are displayed in real
“Explorer” application. Under Windows, each type of files can register both big and small icons in the
system, and “Explorer” will use the registered icons for file displaying. To get the registered icons, we need
to call some special functions. We will implement this method in later sections. Here, we will prepare our
own icons for displaying files. In the sample, two sets of image resources are included in the applications,
one of them will be used for displaying directories and the other for displaying files. Their IDs are
IDB_BITMAP_CLOSEFOLDERBIG, IDB_BITMAP_CLOSEFOLDER, IDB_BITMAP_FILEBIG and IDB_BITMAP_FILE.
In the sample, big icon image list is created from IDB_BITMAP_CLOSEFOLDERBIG and
IDB_BITMAP_FILEBIG. Small icon image list is created from IDB_BITMAP_CLOSEFOLDER and
IDB_BITMAP_FILE. The creation of image list is the same with what we did for the tree view. When an
image list is selected into the list control, we must specify the type of image list. The following portion of
function CExplorerView::ChangeDir() shows how the image lists are selected into the list control in the
sample:
……
……
GetListCtrl().SetImageList(pilSmall, LVSIL_SMALL);
GetListCtrl().SetImageList(pilNormal, LVSIL_NORMAL);
Here pointer pilSmall and pilNormal point to two different image lists. We use LVSIL_SMALL and
LVSIL_NORMAL to specify the type of the image list.
Adding Columns
First we need to add columns to the list control. The columns will appear in the list control window
when the items contained in it are displayed in “Report” style. For each item, usually the small icon
associated with the item and item label will be displayed at the left most column (column 0). For other
columns, we can display text to list other properties of the item.
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