Preparing to Migrate the User Interface

We are ready to start migrating the user interface for our project. As mentioned in the introduction, we do this in steps, ensuring that our application is still usable at every step of the migration process.

The user interface can be viewed as a hierarchy; each top-level window and dialog depends upon a parent (which is another top-level window or dialog). When using Motif XmMainWindow widgets, these should be viewed as two separate entities: the Main Window widget with the popup-menu hierarchy and the View widget contained in the Main Window widget. The View widget depends on the Main Window widget.

We begin migrating the pieces that have no dependencies, and work our way up the dependency tree until all the pieces have been migrated.

The hierarchy for this project looks something like this:

We will begin by migrating and replacing all of the dialogs, then the Main Window widget with popup-menu hierarchy, and finally the View widget.

However, we are not ready to begin just yet. The migration process can be long, but it does not have to be difficult. The Open, Save As, Page Delete and IO Error dialogs use Motif XmFileSelectionBox and XmMessageBox dialogs. Qt provides similar functionality with QFileDialog and QMessageBox, which we can begin using immediately.

The Print dialog is special, however. The Print dialog cannot be replaced until after we have replaced the View widget. Qt provides a complete printing mechanism with QPrinter, but we cannot start using it until we have replaced the View widget.

Removing the Help Dialog