gso 1.0.0

Provides simple interfaces that helps manage and centralize application state.

Global State Observer

GSO is an open-source Python library for managing state. It provides simple interfaces that application data objects and UI elements can easily implement to facilitate syncing them together. It is based on the Observer pattern, and it is inspired by Redux.js.

GSO was originally designed to be used with GUIs built using PySide/PyQt, but it should work with any class-based UI thanks to its abstractness.

How to use

• UI elements should implement the Observer interface, and override the notify(action) method, to update their UI state based on the action.

• Application state should be encapsulated in a class called State. It should hold all observable pieces of data and have a single method: dispatch(action).

• The dispatch(action) method on the State class should be called from the UI elements as a result of a user interaction.

• An Action is an object that describes a UI event that is fired with the intent of changing application state.

• An observable piece of data is any value (or collection of values) in the application state that UI elements depend on.

• Any piece of observable data should be encapsulated in a class that implements the Observable interface, and have any number of methods for updating its values.

• Every update method on an observable piece of data should use the protected member _value in updating, and the protected method of the Observable interface: notify(action), to notify all the attached observers with the update.

• UI elements should observe the observable pieces of data they depend on, this should be done by calling the attach_observer(observer) method on Observables and passing the UI elements as arguments.