| from __future__ import annotations | |
| from rich.console import RenderableType | |
| from textual._easing import EASING | |
| from textual.app import App, ComposeResult | |
| from textual.cli.previews.borders import TEXT | |
| from textual.containers import Container, Horizontal, Vertical | |
| from textual.reactive import Reactive | |
| from textual.scrollbar import ScrollBarRender | |
| from textual.widget import Widget | |
| from textual.widgets import Button, Footer, Static, Input | |
| VIRTUAL_SIZE = 100 | |
| WINDOW_SIZE = 10 | |
| START_POSITION = 0.0 | |
| END_POSITION = float(VIRTUAL_SIZE - WINDOW_SIZE) | |
| class EasingButtons(Widget): | |
| def compose(self) -> ComposeResult: | |
| for easing in sorted(EASING, reverse=True): | |
| yield Button(easing, id=easing) | |
| class Bar(Widget): | |
| position = Reactive.init(START_POSITION) | |
| animation_running = Reactive(False) | |
| DEFAULT_CSS = """ | |
| Bar { | |
| background: $surface; | |
| color: $error; | |
| } | |
| Bar.-active { | |
| background: $surface; | |
| color: $success; | |
| } | |
| """ | |
| def watch_animation_running(self, running: bool) -> None: | |
| self.set_class(running, "-active") | |
| def render(self) -> RenderableType: | |
| return ScrollBarRender( | |
| virtual_size=VIRTUAL_SIZE, | |
| window_size=WINDOW_SIZE, | |
| position=self.position, | |
| style=self.rich_style, | |
| ) | |
| class EasingApp(App): | |
| position = Reactive.init(START_POSITION) | |
| duration = Reactive.var(1.0) | |
| def on_load(self): | |
| self.bind( | |
| "ctrl+p", "focus('duration-input')", description="Focus: Duration Input" | |
| ) | |
| self.bind("ctrl+b", "toggle_dark", description="Toggle Dark") | |
| def compose(self) -> ComposeResult: | |
| self.animated_bar = Bar() | |
| self.animated_bar.position = START_POSITION | |
| duration_input = Input("1.0", placeholder="Duration", id="duration-input") | |
| self.opacity_widget = Static( | |
| f"[b]Welcome to Textual![/]\n\n{TEXT}", id="opacity-widget" | |
| ) | |
| yield EasingButtons() | |
| yield Vertical( | |
| Horizontal( | |
| Static("Animation Duration:", id="label"), duration_input, id="inputs" | |
| ), | |
| Horizontal( | |
| self.animated_bar, | |
| Container(self.opacity_widget, id="other"), | |
| ), | |
| Footer(), | |
| ) | |
| def on_button_pressed(self, event: Button.Pressed) -> None: | |
| self.animated_bar.animation_running = True | |
| def _animation_complete(): | |
| self.animated_bar.animation_running = False | |
| target_position = ( | |
| END_POSITION if self.position == START_POSITION else START_POSITION | |
| ) | |
| self.animate( | |
| "position", | |
| value=target_position, | |
| final_value=target_position, | |
| duration=self.duration, | |
| easing=event.button.id, | |
| on_complete=_animation_complete, | |
| ) | |
| def watch_position(self, value: int): | |
| self.animated_bar.position = value | |
| self.opacity_widget.styles.opacity = 1 - value / END_POSITION | |
| def on_input_changed(self, event: Input.Changed): | |
| if event.sender.id == "duration-input": | |
| new_duration = _try_float(event.value) | |
| if new_duration is not None: | |
| self.duration = new_duration | |
| def action_toggle_dark(self): | |
| self.dark = not self.dark | |
| def _try_float(string: str) -> float | None: | |
| try: | |
| return float(string) | |
| except ValueError: | |
| return None | |
| app = EasingApp(css_path="easing.css") | |
| if __name__ == "__main__": | |
| app.run() | |