dismiss change

Author: willmcgugan

CHANGELOG.md

@@ -10,6 +10,12 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Changed
 
 - `get_content_height` will now return 0 if the renderable is Falsey https://github.com/Textualize/textual/pull/4617
+- Buttons may not be pressed within their "active_effect_duration" to prevent inadvertent activations
+- `Screen.dismiss` is now a noop if the screen isn't active. Previously it would raise a `ScreenStackError`, now it returns `False`.
+
+### Added
+
+- Added `Screen.is_active` 
 
 ## [0.65.2] - 2023-06-06
 

src/textual/screen.py

@@ -342,6 +342,14 @@ def active_bindings(self) -> dict[str, ActiveBinding]:
 
         return bindings_map
 
+    @property
+    def is_active(self) -> bool:
+        """Is the screen active (i.e. visible and top of the stack)?"""
+        try:
+            return self.app.screen is self
+        except Exception:
+            return False
+
     def render(self) -> RenderableType:
         """Render method inherited from widget, used to render the screen's background.
 
@@ -1215,29 +1223,34 @@ def _forward_event(self, event: events.Event) -> None:
     class _NoResult:
         """Class used to mark that there is no result."""
 
-    def dismiss(self, result: ScreenResultType | Type[_NoResult] = _NoResult) -> None:
+    def dismiss(self, result: ScreenResultType | Type[_NoResult] = _NoResult) -> bool:
         """Dismiss the screen, optionally with a result.
 
+        !!! note
+
+            Only the active screen may be dismissed. If you try to dismiss a screen that isn't active,
+            this method will return `False`.
+
         If `result` is provided and a callback was set when the screen was [pushed][textual.app.App.push_screen], then
         the callback will be invoked with `result`.
 
         Args:
             result: The optional result to be passed to the result callback.
 
+        Returns:
+            `True` if the Screen was dismissed, or `False` if the Screen wasn't dismissed due to not being active.
+
         Raises:
             ScreenStackError: If trying to dismiss a screen that is not at the top of
                 the stack.
 
         """
-        if self is not self.app.screen:
-            from .app import ScreenStackError
-
-            raise ScreenStackError(
-                f"Can't dismiss screen {self} that's not at the top of the stack."
-            )
+        if not self.is_active:
+            return False
         if result is not self._NoResult and self._result_callbacks:
             self._result_callbacks[-1](cast(ScreenResultType, result))
         self.app.pop_screen()
+        return True
 
     def action_dismiss(
         self, result: ScreenResultType | Type[_NoResult] = _NoResult

src/textual/widgets/_button.py

@@ -250,7 +250,8 @@ def post_render(self, renderable: RenderableType) -> ConsoleRenderable:
 
     async def _on_click(self, event: events.Click) -> None:
         event.stop()
-        self.press()
+        if not self.has_class("-active"):
+            self.press()
 
     def press(self) -> Self:
         """Animate the button and send the [Pressed][textual.widgets.Button.Pressed] message.
@@ -278,7 +279,8 @@ def _start_active_affect(self) -> None:
 
     def action_press(self) -> None:
         """Activate a press of the button."""
-        self.press()
+        if not self.has_class("-active"):
+            self.press()
 
     @classmethod
     def success(

tests/test_screens.py

@@ -300,8 +300,7 @@ async def key_p(self) -> None:
     app = MyApp()
     async with app.run_test() as pilot:
         await pilot.press("p")
-        with pytest.raises(ScreenStackError):
-            app.bottom.dismiss()
+        assert not app.bottom.dismiss()
 
 
 async def test_dismiss_action():