Enhancing Application Handling
Welcome to Chapter 4! In the previous chapter, we added capabilities for a better selection of a single instance among a possibly large number of models and instances. We started with a simple “move to” function and added a highlight to the current instance as the next step. Then, we implemented a visual selection by using the mouse. Finally, we created a null object to allow selecting no instance at all.
In this chapter, we will focus on the edit mode. First, we will add the capability to switch off all controls and menus by creating a separate view mode. The split between edit and view modes will help us in later chapters to stop all automatic actions when we configure instance settings. Next, we will implement a simplified version of the undo functionality, allowing us to reset the settings of a model instance after applying changes. As the last step, we will implement undo and redo of setting changes on the instance level.
In...
