Merge pull request #5158 from Textualize/faster-screens

Remove `-screen-suspended` class

Author: willmcgugan

src/textual/app.py

@@ -487,6 +487,9 @@ class MyApp(App[None]):
     INLINE_PADDING: ClassVar[int] = 1
     """Number of blank lines above an inline app."""
 
+    SUSPENDED_SCREEN_CLASS: ClassVar[str] = ""
+    """Class to apply to suspended screens, or empty string for no class."""
+
     _PSEUDO_CLASSES: ClassVar[dict[str, Callable[[App], bool]]] = {
         "focus": lambda app: app.app_focus,
         "blur": lambda app: not app.app_focus,

src/textual/screen.py

@@ -1210,7 +1210,8 @@ def _screen_resized(self, size: Size):
 
     def _on_screen_resume(self) -> None:
         """Screen has resumed."""
-        self.remove_class("-screen-suspended")
+        if self.app.SUSPENDED_SCREEN_CLASS:
+            self.remove_class(self.app.SUSPENDED_SCREEN_CLASS)
         self.stack_updates += 1
         self.app._refresh_notifications()
         size = self.app.size
@@ -1230,7 +1231,8 @@ def _on_screen_resume(self) -> None:
 
     def _on_screen_suspend(self) -> None:
         """Screen has suspended."""
-        self.add_class("-screen-suspended")
+        if self.app.SUSPENDED_SCREEN_CLASS:
+            self.add_class(self.app.SUSPENDED_SCREEN_CLASS)
         self.app._set_mouse_over(None)
         self._clear_tooltip()
         self.stack_updates += 1

tests/snapshot_tests/test_snapshots.py

@@ -1960,6 +1960,7 @@ def test_ansi_command_palette(snap_compare):
     """Test command palette on top of ANSI colors."""
 
     class CommandPaletteApp(App[None]):
+        SUSPENDED_SCREEN_CLASS = "-screen-suspended"
         CSS = """
         Label {
             width: 1fr;