def start(self, instance_screen_manager: ScreenManager) -> NoReturn:
"""
Starts the transition. This is automatically called by the
:class:`ScreenManager`.
"""
if self.is_active:
raise ScreenManagerException("start() is called twice!")
self.manager = instance_screen_manager
self._anim = Animation(d=self.duration, s=0)
self._anim.bind(on_progress=self._on_progress,
on_complete=self._on_complete)
if self._direction == "up":
self.add_screen(self.screen_in)
else:
self.add_screen(self.screen_in)
self.add_screen(self.screen_out)
self.screen_in.transition_progress = 0.0
self.screen_in.transition_state = "in"
self.screen_out.transition_progress = 0.0
self.screen_out.transition_state = "out"
self.screen_in.dispatch("on_pre_enter")
self.screen_out.dispatch("on_pre_leave")
self.is_active = True
self._anim.start(self)
self.dispatch("on_progress", 0)
if self._direction == "up":
self.screen_in.y = 0
self.screen_in.opacity = 0
def switch_screen(self, screen_name):
if screen_name in screens.keys():
screen = screens[screen_name](name=screen_name)
self.screen_manager.switch_to(screen)
return
else:
raise ScreenManagerException('Screen {} not found'.format(screen_name))
def switch_tab(self, name_tab):
"""Switching the tab by name."""
if not self.ids.tab_manager.has_screen(name_tab):
raise ScreenManagerException(f"No Screen with name '{name_tab}'.")
self.ids.tab_manager.get_screen(name_tab).dispatch("on_tab_press")
count_index_screen = [
self.ids.tab_manager.screens.index(screen)
for screen in self.ids.tab_manager.screens
if screen.name == name_tab
][0]
numbers_screens = list(range(len(self.ids.tab_manager.screens)))
numbers_screens.reverse()
self.ids.tab_bar.children[numbers_screens.index(
count_index_screen)].dispatch("on_press")
def switch_screen(self, screen_name):
if screen_name in screens.keys():
screen = screens[screen_name](name=screen_name)
self.screen_manager.switch_to(screen)
else:
raise ScreenManagerException('Error')