Application View Controller

AVC is a python module that makes very easy the display and the input of some data of an application program through a GUI.

AVC allow you to:

• free the application program from any code involved in setting or getting widget values;
• avoid widget signals connections and management;
• have a uniform support for the 5 most popular widgets toolkits, GTK, Qt3, Qt4, Tk, wxWidget.
• have a shorter (50% less) and simpler code than solutions based on MVC.

AVC essential concepts

1. Any GUI has a subset of widgets that display values stored in variables of the application program, for example, a text widget can display a string, a spin button can display a float, etc. This functionality is called "view" in computer programming.
2. Almost all "view" widgets can change the displayed value by user interaction, for example, a text widget can edit its content, a spin button can increase/decrease its value by clicking over its up/down arrows, etc. This functionality is called "control" in computer programming.
3. In such a frame of relations between GUI and application, each widget displaying a value can be considered as "connected" to a corresponding application variable.
4. A single application variable can have more than one "view", in other words, it can be displayed by more than one widget. While a widget can be connected to only one variable. So, the elements belonging to a "connection" are one or more widgets and one application variable.
5. But which criteria to use for connecting widgets with variables? Of course, the simplest possible: names matching. It works by giving the same matching name to all the elements of a "connection".

References

• AVC web site