test-kivy-app/kivy_venv/lib/python3.11/site-packages/kivymd/uix/transition/transition.py
2024-09-15 20:57:02 +03:00

498 lines
18 KiB
Python

"""
Components/Transition
=====================
.. rubric::
A set of classes for implementing transitions between application screens.
.. versionadded:: 1.0.0
Changing transitions
--------------------
You have multiple transitions available by default, such as:
- :class:`MDFadeSlideTransition`
state one: the new screen closes the previous screen by lifting from the
bottom of the screen and changing from transparent to non-transparent;
state two: the current screen goes down to the bottom of the screen,
passing from a non-transparent state to a transparent one, thus opening the
previous screen;
.. note::
You cannot control the direction of a slide using the direction attribute.
.. image:: https://github.com/HeaTTheatR/KivyMD-data/raw/master/gallery/kivymddoc/transition-md-fade-slide-transition.gif
:align: center
"""
__all__ = (
"MDFadeSlideTransition",
"MDSlideTransition",
"MDSwapTransition",
"MDTransitionBase",
"MDSharedAxisTransition",
)
from kivy import Logger
from kivy.animation import Animation, AnimationTransition
from kivy.properties import (
DictProperty,
OptionProperty,
NumericProperty,
BooleanProperty,
)
from kivy.uix.screenmanager import (
ScreenManagerException,
SlideTransition,
SwapTransition,
TransitionBase,
)
from kivy.graphics import PopMatrix, PushMatrix, Scale
from kivy.animation import Animation, AnimationTransition
from kivy.metrics import dp
from kivymd.uix.hero import MDHeroFrom, MDHeroTo
from kivymd.uix.screenmanager import MDScreenManager
from kivymd.animation import MDAnimationTransition
class MDTransitionBase(TransitionBase):
"""
TransitionBase is used to animate 2 screens within the
:class:`~kivymd.uix.screenmanager.MDScreenManager`.
For more
information, see in the :class:`~kivy.uix.screenmanager.TransitionBase`
class documentation.
"""
_direction = "in"
# Collection of child widgets of all 'MDHeroFrom' widgets that are
# on the screen, for example:
#
# MDScreen:
#
# MDHeroFrom:
# tag: "kivymd"
#
# FitImage:
#
# MDHeroFrom:
# tag: "kivy"
#
# FitImage:
#
# {
# 'kivy': <kivymd.uix.fitimage.fitimage.FitImage object>,
# 'kivymd': <kivymd.uix.fitimage.fitimage.FitImage object>,
# }
_hero_from_widget_children = DictProperty()
def start(self, instance_screen_manager: MDScreenManager) -> None:
super().start(instance_screen_manager)
{"in": self.animated_hero_in, "out": self.animated_hero_out}[
self._direction
]()
def animated_hero_in(self) -> None:
"""Animates the flight of heroes from screen **A** to screen **B**."""
if self.manager._heroes_data and self.manager.current_heroes:
for hero_from_widget in self.manager.get_hero_from_widget():
for heroes_tag in self.manager.current_heroes:
if heroes_tag == hero_from_widget.tag:
self._check_widget_properties(hero_from_widget)
# Get child widget of the 'MDHeroFrom' container.
hero_widget = hero_from_widget.children[0]
self._hero_from_widget_children[
hero_from_widget.tag
] = hero_widget
# Removing the child widget from the 'MDHeroFrom'
# container.
hero_from_widget.remove_widget(hero_widget)
# We set the size, position of the child widget of the
# 'MDHeroFrom' container and add this widget to the
# root window.
hero_widget.pos = self.screen_out.to_widget(
*hero_from_widget.to_window(*hero_from_widget.pos)
)
hero_widget.size = hero_from_widget.size
self.manager.get_root_window().add_widget(hero_widget)
# Animating widgets added to the root window.
if self.screen_in.heroes_to:
for hero_to_widget in self.screen_in.heroes_to:
self._check_hero_to_widget_tag(
hero_to_widget, hero_from_widget
)
if hero_to_widget.tag == heroes_tag:
Animation(
size=hero_to_widget.size,
d=self.duration,
pos=hero_to_widget.pos,
).start(hero_widget)
hero_from_widget.dispatch(
"on_transform_in",
hero_widget,
self.duration,
)
def animated_hero_out(self) -> None:
"""Animates the flight of heroes from screen **B** to screen **A**."""
if (
self.manager._heroes_data
and self.manager.current_heroes
and self.screen_out.heroes_to
):
for heroes_tag in self.manager.current_heroes:
for hero_to_widget in self.screen_out.heroes_to:
if hero_to_widget.tag == heroes_tag:
hero_from_children = self._hero_from_widget_children[
heroes_tag
]
hero_to_widget.remove_widget(hero_from_children)
self.manager.get_root_window().add_widget(
hero_from_children
)
for (
hero_from_widget
) in self.manager.get_hero_from_widget():
hero_from_widget.dispatch(
"on_transform_out",
self._hero_from_widget_children[
hero_from_widget.tag
],
self.duration,
)
Animation(
pos=self.screen_in.to_widget(
*hero_from_widget.to_window(
*hero_from_widget.pos
)
),
size=hero_from_widget.size,
d=self.duration,
).start(
self._hero_from_widget_children[
hero_from_widget.tag
]
)
def on_complete(self) -> None:
"""
Override method.
See :attr:`kivy.uix.screenmanager.TransitionBase.on_complete'.
"""
super().on_complete()
if self.manager._heroes_data and self.manager.current_heroes:
for hero_from_widget in self.manager.get_hero_from_widget():
for heroes_tag in self.manager.current_heroes:
if heroes_tag == hero_from_widget.tag:
hero_from_children = self._hero_from_widget_children[
heroes_tag
]
self.manager.get_root_window().remove_widget(
hero_from_children
)
# Adding a child widget from the 'MDHeraFrom' container
# to the 'MDHeroTo' container.
if self._direction == "in":
for hero_to_widget in self.screen_in.heroes_to:
if hero_to_widget.tag == heroes_tag:
hero_to_widget.add_widget(
hero_from_children
)
# Restores the child widget for the 'MDHeraFrom'
# container.
elif self._direction == "out":
hero_from_widget.add_widget(hero_from_children)
if self._direction == "out":
self._direction = "in"
else:
self._direction = "out"
# Checks the attributes for the 'self.screen_in' screen.
# Called from the animated_hero_in method.
def _check_widget_properties(self, hero_from_widget: MDHeroFrom):
if not self.screen_in.heroes_to:
raise Exception(
f"The `heroes_to` attribute is not specified for screen "
f"{self.screen_in}"
)
# The 'MDHeroFrom' widget allows you to place only one widget in
# itself.
if len(hero_from_widget.children) > 1:
raise Exception(
f"{hero_from_widget.__class__} accept only one widget"
)
# For new API support.
def _check_hero_to_widget_tag(
self, hero_to_widget: MDHeroTo, hero_from_widget: MDHeroFrom
) -> None:
if not hero_to_widget.tag:
Logger.warning(
"KivyMD: "
f"Set the tag '{hero_from_widget.tag}' "
f"for the {hero_to_widget} widget to the same "
f"as for the {hero_from_widget} widget"
)
hero_to_widget.tag = hero_from_widget.tag
class MDSwapTransition(SwapTransition, MDTransitionBase):
pass
class MDSlideTransition(SlideTransition, MDTransitionBase):
pass
class MDFadeSlideTransition(MDSlideTransition):
def start(self, instance_screen_manager: MDScreenManager) -> None:
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 == "in":
self.add_screen(self.screen_in)
self.animated_hero_in()
else:
self.animated_hero_out()
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 == "in":
self.screen_in.y = 0
self.screen_in.opacity = 0
def on_progress(self, progression: float) -> None:
progression = AnimationTransition.out_quad(progression)
if self._direction == "in":
self.screen_in.y = (
self.manager.y + self.manager.height * progression
) - self.screen_in.height
self.screen_in.opacity = progression
if self._direction == "out":
self.screen_out.y = (
self.manager.y - self.manager.height * progression
)
self.screen_out.opacity = 1 - progression
class MDSharedAxisTransition(MDTransitionBase):
"""
Android default screen transition.
.. versionadded:: 2.0.0
"""
transition_axis = OptionProperty("x", options=["x", "y", "z"])
"""
Axis of the transition. Available values "x", "y", and "z".
.. image:: https://github.com/HeaTTheatR/KivyMD-data/raw/master/gallery/kivymddoc/transition_axis.gif
:align: center
:attr:`transition_axis` is an :class:`~kivy.properties.OptionProperty`
and defaults to `"x"`.
"""
duration = NumericProperty(0.15)
"""
Duration in seconds of the transition. Android recommends these intervals:
.. list-table:: Android transition values (in seconds)
:align: left
:header-rows: 1
* - Name
- value
* - small_1
- 0.075
* - small_2
- 0.15
* - medium_1
- 0.2
* - medium_2
- 0.25
* - large_1
- 0.3
* - large_2
- 0.35
:attr:`duration` is a :class:`~kivy.properties.NumericProperty` and
defaults to 0.15 (= 150ms).
"""
switch_animation = OptionProperty(
"easing_decelerated",
options=[
"easing_standard",
"easing_decelerated",
"easing_accelerated",
"easing_linear",
],
)
"""
Custom material design animation transition.
:attr:`switch_animation` is a :class:`~kivy.properties.OptionProperty` and
defaults to `"easing_decelerated"`.
"""
slide_distance = NumericProperty(dp(15))
"""
Distance to which it slides left, right, bottom or up depending on axis.
:attr:`slide_distance` is a :class:`~kivy.properties.NumericProperty` and
defaults to `dp(15)`.
"""
opposite = BooleanProperty(False)
"""
Decides Transition direction.
:attr:`opposite` is a :class:`~kivy.properties.BooleanProperty` and
defaults to `False`.
"""
_s_map = {} # scale instruction map
_slide_diff = 0
def start(self, manager):
# Transition internal working (for developer only):
# x:
# First half: screen_out opacity 1 -> 0, pos_x: 0 -> - slide distance
# Second half: screen_in opacity 0 -> 1, pos_x: slide distance -> 0
# y:
# First half: screen_out opacity 1 -> 0, pos_y: 0 -> - slide distance
# Second half: screen_in opacity 0 -> 1, pos_y: slide distance -> 0
# z:
# First half: screen_out opacity 1 -> 0, scale: 1 -> relative subtracted area
# Second half: screen_in opacity 0 -> 1, scale: relative subtracted area -> 1
# Save hash of the objects
self.ih = hash(self.screen_in)
self.oh = hash(self.screen_out)
# Init pos
self.screen_in.pos = manager.pos
self.screen_out.pos = manager.pos
if self.transition_axis == "z":
if self.ih not in self._s_map.keys():
# Save scale instructions.
with self.screen_in.canvas.before:
PushMatrix()
self._s_map[self.ih] = Scale()
with self.screen_in.canvas.after:
PopMatrix()
with self.screen_out.canvas.before:
PushMatrix()
self._s_map[self.oh] = Scale()
with self.screen_out.canvas.after:
PopMatrix()
self._s_map[self.oh].origin = [
(manager.pos[0] + manager.width) / 2,
(manager.pos[1] + manager.height) / 2,
]
self._s_map[self.ih].origin = self._s_map[self.oh].origin
# Relative subtracted area.
self._slide_diff = (manager.width - self.slide_distance) * (
manager.height - self.slide_distance
) / (manager.width * manager.height) - 1
elif self.transition_axis in ["x", "y"]:
# Slide distance with opposite logic.
self._slide_diff = (
(1 if self.opposite else -1) * self.slide_distance * 2
)
super().start(manager)
def on_progress(self, progress):
# This code could be simplyfied with setattr, but it's slow
progress = getattr(MDAnimationTransition, self.switch_animation)(progress)
progress_i = progress - 1
progress_d = progress * 2
# First half.
if progress <= 0.5:
# Screen out animation.
if self.transition_axis == "z":
self._s_map[self.oh].xyz = (
*[1 + self._slide_diff * progress_d] * 2,
1,
)
elif self.transition_axis == "x":
self.screen_out.pos = [
self.manager.pos[0] + self._slide_diff * progress,
self.manager.pos[1],
]
else:
self.screen_out.pos = [
self.manager.pos[0],
self.manager.pos[1] - self._slide_diff * progress,
]
self.screen_out.opacity = 1 - progress_d
self.screen_in.opacity = 0
# Second half.
else:
if self.transition_axis == "z":
self._s_map[self.ih].xyz = (
*[1 - self._slide_diff * progress_i * 2] * 2,
1,
)
elif self.transition_axis == "x":
self.screen_in.pos = [
self.manager.pos[0] + self._slide_diff * progress_i,
self.manager.pos[1],
]
else:
self.screen_in.pos = [
self.manager.pos[0],
self.manager.pos[1] - self._slide_diff * progress_i,
]
self.screen_in.opacity = progress_d - 1
self.screen_out.opacity = 0
def on_complete(self):
self.screen_in.pos = self.manager.pos
self.screen_out.pos = self.manager.pos
self.screen_out.opacity = 1
self.screen_in.opacity = 1
if self.oh in self._s_map.keys():
self._s_map[self.oh].xyz = (1, 1, 1)
if self.ih in self._s_map.keys():
self._s_map[self.ih].xyz = (1, 1, 1)
super().on_complete()