Show the content of KeyEvents in enable, and preview the new enable behavior

enable_keys.py

from enable.api import Component, ComponentEditor
from enable.events import KeyEvent
from traits.api import HasTraits, Instance, Str, Bool, Any
from traitsui.api import Item, View, VGroup

import wx
from pyface.qt import QtCore, QtGui
import enable.wx.constants as wx_constants

class KeyEventComponent(Component):

    parent = Any

    def wx_new_behavior_key_event(self, event, gui_event):
        key_code = gui_event.GetKeyCode()
        if key_code in wx_constants.KEY_MAP:
            character = wx_constants.KEY_MAP[key_code]
        elif key_code == wx.WXK_COMMAND:
            character = 'Menu'
        else:
            character = unichr(key_code).lower()

        return KeyEvent(event_type=event.event_type,
                        character=character,
                        x=event.x, y=event.y,
                        control_down=gui_event.ControlDown(),
                        shift_down=gui_event.ShiftDown(),
                        meta_down=gui_event.MetaDown(),
                        event=gui_event,
                        window=event.window)

    def qt_new_behavior_key_event(self, event, gui_event):
        modifiers = gui_event.modifiers()

        character = event.character
        import sys
        if sys.platform == 'darwin':
            # manually switch Meta and Control for Mac OS X
            key_code = gui_event.key()
            if key_code == QtCore.Qt.Key_Control: character = 'Menu'
            elif key_code == QtCore.Qt.Key_Meta: character = 'Control'
            control_down = bool(modifiers & QtCore.Qt.MetaModifier)
            meta_down =  bool(modifiers & QtCore.Qt.ControlModifier)
        else:
            control_down = bool(modifiers & QtCore.Qt.ControlModifier)
            meta_down =  bool(modifiers & QtCore.Qt.MetaModifier)

        # re-package old event according to new criteria
        return KeyEvent(event_type=event.event_type,
                        character=character,
                        x=event.x, y=event.y,
                        alt_down=bool(modifiers & QtCore.Qt.AltModifier),
                        shift_down=bool(modifiers & QtCore.Qt.ShiftModifier),
                        control_down=control_down,
                        meta_down=meta_down,
                        event=gui_event,
                        window=event.window)

    def new_behavior_key_event(self, event, gui_event):
        if isinstance(gui_event, wx._core.KeyEvent):
            return self.wx_new_behavior_key_event(event, gui_event)
        elif isinstance(gui_event, QtGui.QKeyEvent):
            return self.qt_new_behavior_key_event(event, gui_event)

        raise ValueError('Unknown key event: %r' % gui_event)

    def parse_key_event(self, event):
        self.parent.event_repr = repr(event)
        self.parent.character = event.character
        self.parent.alt_down = event.alt_down
        self.parent.control_down = event.control_down
        self.parent.shift_down = event.shift_down
        self.parent.meta_down = getattr(event, 'meta_down', None)

    def normal_key_pressed(self, key_event):
        if self.parent.new_behavior:
            key_event = self.new_behavior_key_event(key_event, key_event.event)
        self.parse_key_event(key_event)


class KeyEventView(HasTraits):

    new_behavior = Bool(False)

    event_repr = Str
    character = Str

    alt_down     = Bool
    control_down = Bool
    shift_down   = Bool
    meta_down    = Bool

    key_event_component = Instance(KeyEventComponent)

    def _key_event_component_default(self):
        return KeyEventComponent(parent=self)

    traits_view = View(
        VGroup(
            Item('new_behavior', label='New behavior?'),
            Item('key_event_component',
                 editor=ComponentEditor(),
                 show_label=False,
                 width=200,height=-50),
            Item('event_repr', style='readonly'),
            Item('character', style='readonly'),
            Item('alt_down', style='readonly'),
            Item('shift_down', style='readonly'),
            Item('control_down', style='readonly'),
            Item('meta_down', style='readonly'),
        ),
        resizable=True,
        title="Key Events"
    )

if __name__ == "__main__":
    KeyEventView().configure_traits()