add blur (#2645)

* add blur

* docstring

* blur on disabled

* snapshot test

* Add test

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Removed
 
 - `Placeholder.reset_color_cycle`
+- Removed `Widget.reset_focus` (now called `Widget.blur`) https://github.com/Textualize/textual/issues/2642
 
 
 ## [0.26.0] - 2023-05-20

src/textual/app.py

@@ -2075,7 +2075,7 @@ class App(Generic[ReturnType], DOMNode):
         Args:
             widget: A Widget to unregister
         """
-        widget.reset_focus()
+        widget.blur()
         if isinstance(widget._parent, Widget):
             widget._parent._nodes._remove(widget)
             widget._detach()

src/textual/screen.py

@@ -386,6 +386,7 @@ class Screen(Generic[ScreenResultType], Widget):
         focusable_widgets = self.focus_chain
         if not focusable_widgets:
             # If there's nothing to focus... give up now.
+            self.set_focus(None)
             return
 
         try:

src/textual/widget.py

@@ -2712,6 +2712,7 @@ class Widget(DOMNode):
 
     def watch_disabled(self) -> None:
         """Update the styles of the widget and its children when disabled is toggled."""
+        self.blur()
         self._update_styles()
 
     def _size_updated(
@@ -3017,8 +3018,10 @@ class Widget(DOMNode):
         self.app.call_later(set_focus, self)
         return self
 
-    def reset_focus(self) -> Self:
-        """Reset the focus (move it to the next available widget).
+    def blur(self) -> Self:
+        """Blur (un-focus) the widget.
+
+        Focus will be moved to the next available widget in the focus chain..
 
         Returns:
             The `Widget` instance.
@@ -3172,7 +3175,7 @@ class Widget(DOMNode):
 
     def _on_hide(self, event: events.Hide) -> None:
         if self.has_focus:
-            self.reset_focus()
+            self.blur()
 
     def _on_scroll_to_region(self, message: messages.ScrollToRegion) -> None:
         self.scroll_to_region(message.region, animate=True)

tests/snapshot_tests/snapshot_apps/blur_on_disabled.py

@@ -0,0 +1,20 @@
+from textual.app import App, ComposeResult
+from textual.widgets import Input
+
+
+class BlurApp(App):
+    BINDINGS = [("f3", "disable")]
+
+    def compose(self) -> ComposeResult:
+        yield Input()
+
+    def on_ready(self) -> None:
+        self.query_one(Input).focus()
+
+    def action_disable(self) -> None:
+        self.query_one(Input).disabled = True
+
+
+if __name__ == "__main__":
+    app = BlurApp()
+    app.run()

tests/snapshot_tests/test_snapshots.py

@@ -514,3 +514,11 @@ def test_select_rebuild(snap_compare):
         SNAPSHOT_APPS_DIR / "select_rebuild.py",
         press=["space", "escape", "tab", "enter", "tab", "space"],
     )
+
+
+def test_blur_on_disabled(snap_compare):
+    # https://github.com/Textualize/textual/issues/2641
+    assert snap_compare(
+        SNAPSHOT_APPS_DIR / "blur_on_disabled.py",
+        press=[*"foo", "f3", *"this should not appear"],
+    )