Checkbox UI element

from ui import Checkbox
contents = [
["Apples", 'apples'], #"Apples" will not be checked on activation
["Oranges", 'oranges', True], #"Oranges" will be checked on activation
["Bananas", 'bananas']]
selected_fruits = Checkbox(checkbox_contents, i, o).activate()
class ui.checkbox.Checkbox(*args, **kwargs)[source]

Implements a checkbox which can be used to enable or disable some functions in your application.


  • contents: list of checkbox entries which was passed either to Checkbox constructor or to checkbox.set_contents().

    Checkbox entry structure is a list, where:
    • entry[0] (entry label) is usually a string which will be displayed in the UI, such as “Option 1”. In case of entry_height > 1, can be a list of strings, each of which represents a corresponding display row occupied by the entry.
    • entry[1] (entry name) is a name returned by the checkbox upon its exit in a dictionary along with its boolean value.
    • entry[2] (entry state) is the default state of the entry (checked or not checked). If not present, assumed to be`` default_state``.

    If you want to set contents after the initalisation, please, use set_contents() method.

  • pointer: currently selected menu element’s number in self.contents.

  • in_foreground : a flag which indicates if checkbox is currently displayed. If it’s not active, inhibits any of menu’s actions which can interfere with other menu or UI element being displayed.

__init__(*args, **kwargs)[source]


  • contents: a list of element descriptions, which can be constructed as described in the Checkbox object’s docstring.
  • i, o: input&output device objects


  • name: Checkbox name which can be used internally and for debugging.
  • entry_height: number of display rows that one checkbox element occupies.
  • default_state: default state for each entry that doesn’t have a state (entry[2]) specified in contents (default: False)
  • final_button_name: label for the last button that confirms the selection (default: "Accept")

A method which is called when UI element needs to start operating. Is blocking, sets up input&output devices, renders the UI element and waits until self.in_foreground is False, while UI element callbacks are executed from the input listener thread.


Sets a flag that signals the UI element’s activate() to return.


A debug method. Useful for hooking up to an input event so that you can see the representation of current UI element’s contents.


A debug method. Useful for hooking up to an input event so that you can see which UI element is currently processing input events.


Sets the UI element contents and triggers pointer recalculation in the view.