textual/examples/easing.py
2021-09-12 15:31:15 +01:00

45 lines
1.5 KiB
Python

from textual._easing import EASING
from textual.app import App
from textual.reactive import Reactive
from textual.views import DockView
from textual.widgets import Placeholder, TreeControl, ScrollView, TreeClick
class EasingApp(App):
"""An app do demonstrate easing."""
side = Reactive(False)
easing = Reactive("linear")
def watch_side(self, side: bool) -> None:
"""Animate when the side changes (False for left, True for right)."""
width = self.easing_view.size.width
animate_x = (width - self.placeholder.size.width) if side else 0
self.placeholder.animate(
"layout_offset_x", animate_x, easing=self.easing, duration=1
)
async def on_mount(self) -> None:
"""Called when application mode is ready."""
self.placeholder = Placeholder()
self.easing_view = DockView()
self.placeholder.style = "white on dark_blue"
tree = TreeControl("Easing", {})
for easing_key in sorted(EASING.keys()):
await tree.add(tree.root.id, easing_key, {"easing": easing_key})
await tree.root.expand()
await self.view.dock(ScrollView(tree), edge="left", size=32)
await self.view.dock(self.easing_view)
await self.easing_view.dock(self.placeholder, edge="left", size=32)
async def handle_tree_click(self, message: TreeClick[dict]) -> None:
"""Called in response to a tree click."""
self.easing = message.node.data.get("easing", "linear")
self.side = not self.side
EasingApp().run(log="textual.log")