SAMPLE: SwSplit.exe Switches Splitter Pane Views in SDI App

ID: Q199515


The information in this article applies to:


SUMMARY

SwSplit.exe is a sample that uses MFC to demonstrate switching between different views in an SDI application. This sample allows the user to select a single view or multiple views. Multiple views are displayed in the panes of a splitter window. The sample demonstrates how you can show different views (some in a nested splitter window) based on the selection in a tree view.


MORE INFORMATION

The following file is available for download from the Microsoft Software Library:

SwSplit.exe
Release Date: Feb-26-1999

For more information about downloading files from the Microsoft Software Library, please see the following article in the Microsoft Knowledge Base:
Q119591 How to Obtain Microsoft Support Files from Online Services


The MFC AppWizard can create two basic frameworks for applications that have document/view architecture support: single document interface (SDI) and multiple document interface (MDI). SDI and MDI are starting points for you to build an application that can look different from AppWizard-produced applications.

Microsoft Outlook 98 is an example of a popular user-interface (UI) structure. The Outlook 98 UI structure has a multi-pane splitter window, where different views can appear in different panes. The particular views displayed can depend on which items are selected in other UI objects (for example, a tree view). Certain selections can bring up a splitter window within an existing splitter window.

This type of application UI design is not really MDI because it only has one frame window. MDI applications have multiple child frame windows within the main frame window. However, the Outlook 98 design can display one or more different types of views. It is not usually clear how to achieve this type of interface with the SDI framework. The SwSplit.exe sample shows you how to create this type of a UI design using MFC and the SDI framework produced by the MFC AppWizard. NOTE: Outlook 98 does not use MFC.

SwSplit.exe uses static splitter windows. A static splitter window has a fixed number of panes. This differs from a dynamic splitter window where you can change the number of panes. If a user wants to change the number or the orientation of the panes in SwSplit.exe, the splitter window is destroyed and a new splitter window with the desired pane structure is created in its place. In this process, the original views are also destroyed and new views are created to fill the new splitter panes.

SwSplit.exe uses a list view, edit view, tree view and three different form views. The code that switches the views makes it easy to switch to other types of views. Here is an example of part of the code that creates a splitter view, its panes, and the views that fill those panes. CSplitterView has a member object of the CSplitterWnd-derived class, represented by the variable m_wndSplitter. Two views are created to fill a window that is split by a vertical splitter bar. These views are based on the run-time classes passed into the CreateView function. The left pane gets a view based on CMyTreeView, and the right pane gets a view based on CFormView1.


int CSplitterView::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
   if (CView::OnCreate(lpCreateStruct) == -1)
      return -1;
   m_wndSplitter.CreateStatic(this, 1, 2);
   CCreateContext* pContext = (CCreateContext*)lpCreateStruct->lpCreateParams:
   m_wndSplitter.CreateView(0, 0, RUNTIME_CLASS(CMyTreeView), CSize(0,0), pContext);
   m_wndSplitter.CreateView(0, 1, RUNTIME_CLASS(CFormView1), CSize(0,0), pContext);

   return 0;
} 


SwSplit.exe demonstrates how to create, persist, and display data in this type of a multi-view SDI application. A file is opened and the data is saved on a transaction basis. This is similar to the CHKBOOK MDI sample that comes with Visual C++. In addition to showing transaction-based saving of data in an SDI application, SwSplit.exe automatically loads the most recently-used file at start up. SwSplit.exe reads the application's registry entries for the most recently-used files. Although some users may need to save the data on a transaction basis, it complicates things. It is much easier to let the MFC framework persist the data in the standard way. The standard way involves saving the data all at once when the user chooses to save it or when closing the document. You can use the standard way by implementing the document class' Serialize function. When you can, it is best to let MFC do the work for you. You get a more robust and maintainable solution that way.

This sample demonstrates how to alter the menu and toolbar to suit the active view. The only view-specific items that are altered for a particular view are the toolbar buttons and menu items that show and remove FormView3. All other menu items and toolbar buttons are displayed for all views. The framework's command UI updating takes care of enabling or disabling them. For example, the menu items and toolbar buttons that pertain to the editview in this sample (that is, undo, cut, copy, paste, and print) are displayed for all views. This is the typical way to handle it. The menu items and toolbar buttons are unavailable when the appropriate view is not displayed or does not have the focus. NOTE: The same could have been done for the toolbar buttons and menu items that show and remove FormView3.

SwSplit.exe also demonstrates how to display non-standard background colors in views and certain controls. You need to be careful when using this feature in your own application. Some users might not like your colors. By changing the background colors you restrict the users ability to apply a personal color scheme by changing these settings in the Control Panel. In addition, playing with colors might affect the accessibility of your application. For example, some users might be color blind.

The VIEWEX and COLLECT samples might also be helpful. Both samples come with Visual C++. VIEWEX uses the MDI architecture, and shows you how to use different types of static splitter windows in separate child frame windows. The COLLECT sample illustrates the MFC collection classes, and it demonstrates how to display different views in an SDI application. However, none of the views in COLLECT involve splitter windows.

Additional query words: CTreeView OnCmdMsg m_dwDefaultStyle CCmdUI ON_UPDATE_COMMAND_UI CreateView


Keywords          : kbfile kbsample kbDocView kbMFC KbUIDesign kbVC420 kbVC500 kbVC600 
Version           : winnt:4.2,5.0,6.0
Platform          : winnt 
Issue type        : kbhowto 

Last Reviewed: February 27, 1999