DeUI: Declarative UI Wrapper Framework for Pure Python

Declare User Interface by Pure Python Code.

Motivation

1. Write pure Python code to declare User Interface, instead of using external layout file
2. Give a flexible and efficient way to wrap existing UI frameworks
3. Allow any users, including corporations, to use this framework both for OSS and proprietary projects

Solutions

1. Use with statement to bind view context

   class RootComponent(ViewComponent):
       def body():
           with MainView(some_parameter=1.0):
               # Conditional layouts can be declared with pure Python code
               if some_state == SomeState.pattern_A:
                   with SomeComponent():
                       SomeView()
               else:
                   with AnotherComponent():
                       AnotherView()

2. Use __new__ definitions to separate view hierarchies and actual widgets

   instance = SomeWidget()
   
   print(isinstance(instance, Widget))
   # -> False
   print(isinstance(instance, View))
   # -> True
   
   # actual widget is created by lazy evaluation when needed.
   print(isinstance(instance.get_initial_widget(), Widget))
   # -> True

3. Release core components under MIT license, and give a room for choice of actual UI frameworks for implementation

Roadmaps

• render widgets by updating only changed parts of the view hierarchy
• thread-safe view context binding
• bind properties and states of actual widgets
• provide wraps for existing UI frameworks

Misc

• DeUI is, of course, the shortened name of Declarative UI.

  The logo is inspired by Chinese sweets Jin Deui, which is sesame-coated and fried rice cake wrapping lotus, black bean, or red bean paste.