Bump0260 (#2617)

* full map

* docstring changelog

* changelog

* simplify, add comment

CHANGELOG.md

@@ -5,6 +5,15 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [0.26.0] - 2023-05-20
+
+### Added
+
+- Added Widget.can_view
+
+### Changed
+
+- Textual will now scroll focused widgets to center if not in view
 
 ## [0.25.0] - 2023-05-17
 
@@ -965,6 +974,7 @@ https://textual.textualize.io/blog/2022/11/08/version-040/#version-040
 - New handler system for messages that doesn't require inheritance
 - Improved traceback handling
 
+[0.26.0]: https://github.com/Textualize/textual/compare/v0.25.0...v0.26.0
 [0.25.0]: https://github.com/Textualize/textual/compare/v0.24.1...v0.25.0
 [0.24.1]: https://github.com/Textualize/textual/compare/v0.24.0...v0.24.1
 [0.24.0]: https://github.com/Textualize/textual/compare/v0.23.0...v0.24.0

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "textual"
-version = "0.25.0"
+version = "0.26.0"
 homepage = "https://github.com/Textualize/textual"
 description = "Modern Text User Interface framework"
 authors = ["Will McGugan <will@textualize.io>"]

src/textual/_compositor.py

@@ -806,7 +806,7 @@ class Compositor:
         if self.root is None:
             raise errors.NoWidget("Widget is not in layout")
         try:
-            if self._full_map is not None:
+            if not self._full_map_invalidated:
                 try:
                     return self._full_map[widget]
                 except KeyError:

src/textual/screen.py

@@ -246,6 +246,9 @@ class Screen(Generic[ScreenResultType], Widget):
     @property
     def focus_chain(self) -> list[Widget]:
         """A list of widgets that may receive focus, in focus order."""
+        # TODO: Calculating a focus chain is moderately expensive.
+        # Suspect we can move focus without calculating the entire thing again.
+
         widgets: list[Widget] = []
         add_widget = widgets.append
         stack: list[Iterator[Widget]] = [iter(self.focusable_children)]
@@ -283,6 +286,8 @@ class Screen(Generic[ScreenResultType], Widget):
                 is not `None`, then it is guaranteed that the widget returned matches
                 the CSS selectors given in the argument.
         """
+        # TODO: This shouldn't be required
+        self._compositor._full_map_invalidated = True
         if not isinstance(selector, str):
             selector = selector.__name__
         selector_set = parse_selectors(selector)
@@ -469,11 +474,16 @@ class Screen(Generic[ScreenResultType], Widget):
                 self.focused = widget
                 # Send focus event
                 if scroll_visible:
-                    self.screen.scroll_to_widget(widget)
+
+                    def scroll_to_center(widget: Widget) -> None:
+                        """Scroll to center (after a refresh)."""
+                        if widget.has_focus and not self.screen.can_view(widget):
+                            self.screen.scroll_to_center(widget)
+
+                    self.call_after_refresh(scroll_to_center, widget)
                 widget.post_message(events.Focus())
                 focused = widget
 
-                self._update_focus_styles(self.focused, widget)
                 self.log.debug(widget, "was focused")
 
         self._update_focus_styles(focused, blurred)

src/textual/widget.py

@@ -2267,13 +2267,12 @@ class Widget(DOMNode):
 
         while isinstance(widget.parent, Widget) and widget is not self:
             container = widget.parent
-
             if widget.styles.dock:
                 scroll_offset = Offset(0, 0)
             else:
                 scroll_offset = container.scroll_to_region(
                     region,
-                    spacing=widget.parent.gutter + widget.dock_gutter,
+                    spacing=widget.gutter + widget.dock_gutter,
                     animate=animate,
                     speed=speed,
                     duration=duration,
@@ -2286,15 +2285,17 @@ class Widget(DOMNode):
 
             # Adjust the region by the amount we just scrolled it, and convert to
             # it's parent's virtual coordinate system.
+
             region = (
                 (
                     region.translate(-scroll_offset)
                     .translate(-widget.scroll_offset)
-                    .translate(container.virtual_region.offset)
+                    .translate(container.virtual_region_with_margin.offset)
                 )
                 .grow(container.styles.margin)
-                .intersection(container.virtual_region)
+                .intersection(container.virtual_region_with_margin)
             )
+
             widget = container
         return scrolled
 
@@ -2483,6 +2484,30 @@ class Widget(DOMNode):
             force=force,
         )
 
+    def can_view(self, widget: Widget) -> bool:
+        """Check if a given widget is in the current view (scrollable area).
+
+        Note: This doesn't necessarily equate to a widget being visible.
+        There are other reasons why a widget may not be visible.
+
+        Args:
+            widget: A widget that is a descendant of self.
+
+        Returns:
+            True if the entire widget is in view, False if it is partially visible or not in view.
+        """
+        if widget is self:
+            return True
+
+        region = widget.region
+        node: Widget = widget
+
+        while isinstance(node.parent, Widget) and node is not self:
+            if region not in node.parent.scrollable_content_region:
+                return False
+            node = node.parent
+        return True
+
     def __init_subclass__(
         cls,
         can_focus: bool | None = None,

src/textual/widgets/_select.py

@@ -9,6 +9,7 @@ from rich.text import Text
 from .. import events, on
 from ..app import ComposeResult
 from ..containers import Horizontal, Vertical
+from ..css.query import NoMatches
 from ..message import Message
 from ..reactive import var
 from ..widgets import Static
@@ -298,17 +299,22 @@ class Select(Generic[SelectType], Vertical, can_focus=True):
     def _watch_value(self, value: SelectType | None) -> None:
         """Update the current value when it changes."""
         self._value = value
-        if value is None:
-            self.query_one(SelectCurrent).update(None)
+        try:
+            select_current = self.query_one(SelectCurrent)
+        except NoMatches:
+            pass
         else:
-            for index, (prompt, _value) in enumerate(self._options):
-                if _value == value:
-                    select_overlay = self.query_one(SelectOverlay)
-                    select_overlay.highlighted = index
-                    self.query_one(SelectCurrent).update(prompt)
-                    break
-            else:
+            if value is None:
                 self.query_one(SelectCurrent).update(None)
+            else:
+                for index, (prompt, _value) in enumerate(self._options):
+                    if _value == value:
+                        select_overlay = self.query_one(SelectOverlay)
+                        select_overlay.highlighted = index
+                        self.query_one(SelectCurrent).update(prompt)
+                        break
+                else:
+                    self.query_one(SelectCurrent).update(None)
 
     def compose(self) -> ComposeResult:
         """Compose Select with overlay and current value."""