Merge pull request #6137 from Textualize/alternative-footer-flicker-fix

delay update for footer

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Reduced number of layout operations required to update the screen https://github.com/Textualize/textual/pull/6108
 - The :hover pseudo-class no applies to the first widget under the mouse with a hover style set https://github.com/Textualize/textual/pull/6132
 - The footer key hover background is more visible https://github.com/Textualize/textual/pull/6132
+- Made `App.delay_update` public https://github.com/Textualize/textual/pull/6137
 
 ### Added
 

src/textual/app.py

@@ -1019,10 +1019,11 @@ class App(Generic[ReturnType], DOMNode):
         if not self._batch_count:
             self.check_idle()
 
-    def _delay_update(self, delay: float = 0.05) -> None:
+    def delay_update(self, delay: float = 0.05) -> None:
         """Delay updates for a short period of time.
 
         May be used to mask a brief transition.
+        Consider this method only if you aren't able to use `App.batch_update`.
 
         Args:
             delay: Delay before updating.
@@ -1035,7 +1036,7 @@ class App(Generic[ReturnType], DOMNode):
             if not self._batch_count:
                 self.screen.refresh()
 
-        self.set_timer(delay, end_batch, name="_delay_update")
+        self.set_timer(delay, end_batch, name="delay_update")
 
     @contextmanager
     def _context(self) -> Generator[None, None, None]:

src/textual/command.py

@@ -1230,7 +1230,7 @@ class CommandPalette(SystemModalScreen[None]):
                 # decide what to do with it (hopefully it'll run it).
                 self._cancel_gather_commands()
                 self.app.post_message(CommandPalette.Closed(option_selected=True))
-                self.app._delay_update()
+                self.app.delay_update()
                 self.dismiss()
                 self.app.call_later(self._selected_command.command)
 

src/textual/widgets/_footer.py

@@ -130,7 +130,7 @@ class FooterKey(Widget):
         label_text.stylize_before(self.rich_style)
         return label_text
 
-    async def on_mouse_down(self) -> None:
+    def on_mouse_down(self) -> None:
         if self._disabled:
             self.app.bell()
         else:
@@ -332,7 +332,7 @@ class Footer(ScrollableContainer, can_focus=False, can_focus_children=False):
         if not screen.app.app_focus:
             return
         if self.is_attached and screen is self.screen:
-            await self.recompose()
+            self.call_after_refresh(self.recompose)
 
     def _on_mouse_scroll_down(self, event: events.MouseScrollDown) -> None:
         if self.allow_horizontal_scroll:
@@ -351,12 +351,7 @@ class Footer(ScrollableContainer, can_focus=False, can_focus_children=False):
     async def on_mount(self) -> None:
         await asyncio.sleep(0)
         self.call_next(self.bindings_changed, self.screen)
-
-        def bindings_changed(screen: Screen) -> None:
-            """Update bindings after a short delay to avoid flicker."""
-            self.call_after_refresh(self.bindings_changed, screen)
-
-        self.screen.bindings_updated_signal.subscribe(self, bindings_changed)
+        self.screen.bindings_updated_signal.subscribe(self, self.bindings_changed)
 
     def on_unmount(self) -> None:
         self.screen.bindings_updated_signal.unsubscribe(self)

src/textual/widgets/_help_panel.py

@@ -79,7 +79,10 @@ class HelpPanel(Widget):
     DEFAULT_CLASSES = "-textual-system"
 
     def on_mount(self):
-        self.watch(self.screen, "focused", self.update_help)
+        def update_help(focused_widget: Widget | None):
+            self.update_help(focused_widget)
+
+        self.watch(self.screen, "focused", update_help)
 
     def update_help(self, focused_widget: Widget | None) -> None:
         """Update the help for the focused widget.

src/textual/widgets/_key_panel.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 from collections import defaultdict
-from functools import partial
 from itertools import groupby
 from operator import itemgetter
 from typing import TYPE_CHECKING
@@ -164,16 +163,17 @@ class KeyPanel(VerticalScroll, can_focus=False):
         yield BindingsTable(shrink=True, expand=False)
 
     async def on_mount(self) -> None:
+        mount_screen = self.screen
+
         async def bindings_changed(screen: Screen) -> None:
             """Update bindings."""
             if not screen.app.app_focus:
                 return
-            if self.is_attached and screen is self.screen:
-                self.refresh(recompose=True)
+            if self.is_attached and screen is mount_screen:
+                await self.recompose()
 
         def _bindings_changed(screen: Screen) -> None:
-            """Update bindings after a short delay."""
-            screen.set_timer(1 / 20, partial(bindings_changed, screen))
+            self.call_after_refresh(bindings_changed, screen)
 
         self.set_class(self.app.ansi_color, "-ansi-scrollbar")
         self.screen.bindings_updated_signal.subscribe(self, _bindings_changed)

tests/test_modal.py

@@ -89,10 +89,11 @@ async def test_modal_pop_screen():
     app = ModalApp()
     async with app.run_test() as pilot:
         # Pause to ensure the footer is fully composed to avoid flakiness in CI
-        await pilot.pause(0.4)
+        await pilot.pause()
         await app.wait_for_refresh()
+        await pilot.pause()
         # Check clicking the footer brings up the quit screen
-        await pilot.click(Footer)
+        await pilot.click(Footer, offset=(1, 0))
         await pilot.pause()
         assert isinstance(pilot.app.screen, QuitScreen)
         # Check activating the quit button exits the app