Zero or One Document Interface (ZODI)

Environment: VC6

What’s This?

This article describes how to create a single-document application using a multi-document interface. You may have zero or one documents at a time.

I’ve written a CMultiDocTemplate-derived class, CZoDocTemplate. It overrides the OpenDocumentFile function. OpenDocumentFile works like CSingleDocTemplate; it reinitializes a created document instead of creating one more document. If there is no opened document, a new document is created as in an MDI case. If you create several document templates, you will have a maximum of one document per template.

To Create Your Own ZODI Application

1. Create an MDI application with AppWizard.
2. Add ZoDocTemplate.h and ZoDocTemplate.cpp in your project, named <your app>.
3. Include ZoDocTemplate.h in <your app>.cpp.
4. In the InitInstance function, replace:

       CMultiDocTemplate* pDocTemplate;
       pDocTemplate = new CMultiDocTemplate(…);
   

   with

       CZoDocTemplate* pDocTemplate;
       pDocTemplate = new CZoDocTemplate(…);
   

Similar Article

Here is a similar article, MSDI. In it, I present another, simpler, way of MSDI implementation. In the MSDI example, when opening a new document, the created one is destroyed and a new one is created. In ZODI, the existing document is reinitialized as in the SDI case.

Downloads

Download demo project – 21 Kb

Download simple exe – 8 Kb

Download source – 4 Kb