kivy/examples/demo/multistroke/main.py

#!/usr/bin/env python
from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.uix.gesturesurface import GestureSurface
from kivy.uix.screenmanager import ScreenManager, Screen, SlideTransition
from kivy.uix.label import Label
from kivy.multistroke import Recognizer

# Local libraries
from historymanager import GestureHistoryManager
from gesturedatabase import GestureDatabase
from settings import MultistrokeSettingsContainer


class MainMenu(GridLayout):
    pass


class MultistrokeAppSettings(MultistrokeSettingsContainer):
    pass


class MultistrokeApp(App):

    def goto_database_screen(self, *l):
        self.database.import_gdb()
        self.manager.current = 'database'

    def handle_gesture_cleanup(self, surface, g, *l):
        if hasattr(g, '_result_label'):
            surface.remove_widget(g._result_label)

    def handle_gesture_discard(self, surface, g, *l):
        # Don't bother creating Label if it's not going to be drawn
        if surface.draw_timeout == 0:
            return

        text = '[b]Discarded:[/b] Not enough input'
        g._result_label = Label(text=text, markup=True, size_hint=(None, None),
            center=(g.bbox['minx'], g.bbox['miny']))
        self.surface.add_widget(g._result_label)

    def handle_gesture_complete(self, surface, g, *l):
        result = self.recognizer.recognize(g.get_vectors())
        result._gesture_obj = g
        result.bind(on_complete=self.handle_recognize_complete)

    def handle_recognize_complete(self, result, *l):
        self.history.add_recognizer_result(result)

        # Don't bother creating Label if it's not going to be drawn
        if self.surface.draw_timeout == 0:
            return

        best = result.best
        if best['name'] is None:
            text = '[b]No match[/b]'
        else:
            text = 'Name: [b]%s[/b]\nScore: [b]%f[/b]\nDistance: [b]%f[/b]' % (
                    best['name'], best['score'], best['dist'])

        g = result._gesture_obj
        g._result_label = Label(text=text, markup=True, size_hint=(None, None),
            center=(g.bbox['minx'], g.bbox['miny']))
        self.surface.add_widget(g._result_label)

    def build(self):
        # Setting NoTransition breaks the "history" screen! Possibly related
        # to some inexplicable rendering bugs on my particular system
        self.manager = ScreenManager(transition=SlideTransition(
                duration=.15))
        self.recognizer = Recognizer()

        # Setup the GestureSurface and bindings to our Recognizer
        surface = GestureSurface(line_width=2, draw_bbox=True,
                use_random_color=True)
        surface_screen = Screen(name='surface')
        surface_screen.add_widget(surface)
        self.manager.add_widget(surface_screen)

        surface.bind(on_gesture_discard=self.handle_gesture_discard)
        surface.bind(on_gesture_complete=self.handle_gesture_complete)
        surface.bind(on_gesture_cleanup=self.handle_gesture_cleanup)
        self.surface = surface

        # History is the list of gestures drawn on the surface
        history = GestureHistoryManager()
        history_screen = Screen(name='history')
        history_screen.add_widget(history)
        self.history = history
        self.manager.add_widget(history_screen)

        # Database is the list of gesture templates in Recognizer
        database = GestureDatabase(recognizer=self.recognizer)
        database_screen = Screen(name='database')
        database_screen.add_widget(database)
        self.database = database
        self.manager.add_widget(database_screen)

        # Settings screen
        app_settings = MultistrokeAppSettings()
        ids = app_settings.ids

        ids.max_strokes.bind(value=surface.setter('max_strokes'))
        ids.temporal_win.bind(value=surface.setter('temporal_window'))
        ids.timeout.bind(value=surface.setter('draw_timeout'))
        ids.line_width.bind(value=surface.setter('line_width'))
        ids.draw_bbox.bind(value=surface.setter('draw_bbox'))
        ids.use_random_color.bind(value=surface.setter('use_random_color'))

        settings_screen = Screen(name='settings')
        settings_screen.add_widget(app_settings)
        self.manager.add_widget(settings_screen)

        # Wrap in a gridlayout so the main menu is always visible
        layout = GridLayout(cols=1)
        layout.add_widget(self.manager)
        layout.add_widget(MainMenu())
        return layout


if __name__ in ('__main__', '__android__'):
    MultistrokeApp().run()