fix basic

sandbox/will/basic.css

@@ -13,10 +13,15 @@
 }
 
 App > Screen {
-  layout: dock;
+    
-  docks: side=left/1;
   background: $surface;
   color: $text-surface; 
+  layers: sidebar;
+
+  color: $text-background;
+  background: $background;
+  layout: vertical;
+  
 }
 
 DataTable {
@@ -31,11 +36,12 @@ DataTable {
 #sidebar {
   color: $text-panel;
   background: $panel;
-  dock: side;
+  dock: left;
   width: 30;
   offset-x: -100%;
-  layout: dock;
+  
   transition: offset 500ms in_out_cubic;
+  layer: sidebar;
 }
 
 #sidebar.-active {
@@ -71,14 +77,7 @@ DataTable {
   height: 1;
   content-align: center middle;
   
-   
+  dock: top;
-}
-
-#content {
-  color: $text-background;
-  background: $background;
-  layout: vertical;
-  overflow-y: scroll;
 }
 
 
@@ -168,6 +167,7 @@ Tweet.scroll-horizontal TweetBody {
   height: 1;
   
   content-align: center middle;
+  dock:bottom;
 }
 
 

sandbox/will/basic.py

@@ -1,9 +1,9 @@
 from rich.console import RenderableType
-from rich.style import Style
+
 from rich.syntax import Syntax
 from rich.text import Text
 
-from textual.app import App
+from textual.app import App, ComposeResult
 from textual.reactive import Reactive
 from textual.widget import Widget
 from textual.widgets import Static, DataTable
@@ -98,45 +98,45 @@ class BasicApp(App, css_path="basic.css"):
         """Bind keys here."""
         self.bind("s", "toggle_class('#sidebar', '-active')")
 
-    def on_mount(self):
+    def compose(self) -> ComposeResult:
-        """Build layout here."""
-
         table = DataTable()
         self.scroll_to_target = Tweet(TweetBody())
-        self.mount(
+
-            header=Static(
+        yield Static(
-                Text.from_markup(
+            Text.from_markup(
-                    "[b]This is a [u]Textual[/u] app, running in the terminal"
+                "[b]This is a [u]Textual[/u] app, running in the terminal"
-                ),
-            ),
-            content=Widget(
-                Tweet(TweetBody()),
-                Widget(
-                    Static(Syntax(CODE, "python"), classes="code"),
-                    classes="scrollable",
-                ),
-                table,
-                Error(),
-                Tweet(TweetBody(), classes="scrollbar-size-custom"),
-                Warning(),
-                Tweet(TweetBody(), classes="scroll-horizontal"),
-                Success(),
-                Tweet(TweetBody(), classes="scroll-horizontal"),
-                Tweet(TweetBody(), classes="scroll-horizontal"),
-                Tweet(TweetBody(), classes="scroll-horizontal"),
-                Tweet(TweetBody(), classes="scroll-horizontal"),
-                Tweet(TweetBody(), classes="scroll-horizontal"),
-            ),
-            footer=Widget(),
-            sidebar=Widget(
-                Widget(classes="title"),
-                Widget(classes="user"),
-                OptionItem(),
-                OptionItem(),
-                OptionItem(),
-                Widget(classes="content"),
             ),
+            id="header",
         )
+        yield from (
+            Tweet(TweetBody()),
+            Widget(
+                Static(Syntax(CODE, "python"), classes="code"),
+                classes="scrollable",
+            ),
+            table,
+            Error(),
+            Tweet(TweetBody(), classes="scrollbar-size-custom"),
+            Warning(),
+            Tweet(TweetBody(), classes="scroll-horizontal"),
+            Success(),
+            Tweet(TweetBody(), classes="scroll-horizontal"),
+            Tweet(TweetBody(), classes="scroll-horizontal"),
+            Tweet(TweetBody(), classes="scroll-horizontal"),
+            Tweet(TweetBody(), classes="scroll-horizontal"),
+            Tweet(TweetBody(), classes="scroll-horizontal"),
+        )
+        yield Widget(id="footer")
+        yield Widget(
+            Widget(classes="title"),
+            Widget(classes="user"),
+            OptionItem(),
+            OptionItem(),
+            OptionItem(),
+            Widget(classes="content"),
+            id="sidebar",
+        )
+
         table.add_column("Foo", width=20)
         table.add_column("Bar", width=20)
         table.add_column("Baz", width=20)

sandbox/will/dock.py

@@ -41,8 +41,9 @@ class DockApp(App):
 
         for n, color in zip(range(5), ["red", "green", "blue", "yellow", "magenta"]):
             thing = Static(f"Thing {n}", id=f"#thing{n}")
+            thing.styles.border = ("heavy", "rgba(0,0,0,0.2)")
             thing.styles.background = f"{color} 20%"
-            thing.styles.height = 5
+            thing.styles.height = 15
             yield thing
 
 

src/textual/_arrange.py

@@ -5,16 +5,25 @@ from fractions import Fraction
 from typing import TYPE_CHECKING
 
 from .geometry import Region, Size, Spacing
-from ._layout import ArrangeResult, WidgetPlacement
+from ._layout import DockArrangeResult, WidgetPlacement
 from ._partition import partition
 
 
 if TYPE_CHECKING:
-    from ._layout import ArrangeResult
     from .widget import Widget
 
 
-def arrange(widget: Widget, size: Size, viewport: Size) -> ArrangeResult:
+def arrange(widget: Widget, size: Size, viewport: Size) -> DockArrangeResult:
+    """Arrange widgets by applying docks and calling layouts
+
+    Args:
+        widget (Widget): The parent (container) widget.
+        size (Size): The size of the available area.
+        viewport (Size): The size of the viewport (terminal).
+
+    Returns:
+        tuple[list[WidgetPlacement], set[Widget], Spacing]: Widget arrangement information.
+    """
     display_children = [child for child in widget.children if child.display]
 
     arrange_widgets: set[Widget] = set()
@@ -31,7 +40,8 @@ def arrange(widget: Widget, size: Size, viewport: Size) -> ArrangeResult:
 
     _WidgetPlacement = WidgetPlacement
 
-    top_z = 2**32 - 1
+    # TODO: This is a bit of a fudge, need to ensure it is impossible for layouts to generate this value
+    top_z = 2**31 - 1
 
     scroll_spacing = Spacing()
 
@@ -47,23 +57,15 @@ def arrange(widget: Widget, size: Size, viewport: Size) -> ArrangeResult:
         for dock_widget in dock_widgets:
             edge = dock_widget.styles.dock
 
-            (
+            fraction_unit = Fraction(
-                widget_width_fraction,
+                size.height if edge in ("top", "bottom") else size.width
-                widget_height_fraction,
-                margin,
-            ) = dock_widget.get_box_model(
-                size,
-                viewport,
-                Fraction(size.height if edge in ("top", "bottom") else size.width),
             )
+            box_model = dock_widget.get_box_model(size, viewport, fraction_unit)
+            widget_width_fraction, widget_height_fraction, margin = box_model
 
             widget_width = int(widget_width_fraction) + margin.width
             widget_height = int(widget_height_fraction) + margin.height
 
-            align_offset = dock_widget.styles.align_size(
-                (widget_width, widget_height), size
-            )
-
             if edge == "bottom":
                 dock_region = Region(
                     0, height - widget_height, widget_width, widget_height
@@ -80,13 +82,18 @@ def arrange(widget: Widget, size: Size, viewport: Size) -> ArrangeResult:
                     width - widget_width, 0, widget_width, widget_height
                 )
                 right = max(right, dock_region.width)
+            else:
+                raise AssertionError("invalid value for edge")
 
+            align_offset = dock_widget.styles.align_size(
+                (widget_width, widget_height), size
+            )
             dock_region = dock_region.shrink(margin).translate(align_offset)
             add_placement(_WidgetPlacement(dock_region, dock_widget, top_z, True))
 
         dock_spacing = Spacing(top, right, bottom, left)
         region = size.region.shrink(dock_spacing)
-        layout_placements, _layout_widgets, spacing = widget.layout.arrange(
+        layout_placements, _layout_widgets = widget.layout.arrange(
             widget, layout_widgets, region.size
         )
         if _layout_widgets:
@@ -101,26 +108,4 @@ def arrange(widget: Widget, size: Size, viewport: Size) -> ArrangeResult:
 
         placements.extend(layout_placements)
 
-    result = ArrangeResult(placements, arrange_widgets, scroll_spacing)
+    return placements, arrange_widgets, scroll_spacing
-    return result
-
-    # dock_spacing = Spacing(top, right, bottom, left)
-    # region = region.shrink(dock_spacing)
-
-    # placements, placement_widgets, spacing = widget.layout.arrange(
-    #     widget, layout_widgets, region.size
-    # )
-    # dock_spacing += spacing
-
-    # placement_offset = region.offset
-    # if placement_offset:
-    #     placements = [
-    #         _WidgetPlacement(_region + placement_offset, widget, order, fixed)
-    #         for _region, widget, order, fixed in placements
-    #     ]
-
-    # return ArrangeResult(
-    #     (dock_placements + placements),
-    #     placement_widgets.union(layout_widgets),
-    #     dock_spacing,
-    # )

src/textual/_layout.py

@@ -17,12 +17,8 @@ if TYPE_CHECKING:
     from .widget import Widget
 
 
-class ArrangeResult(NamedTuple):
+ArrangeResult: TypeAlias = "tuple[list[WidgetPlacement], set[Widget]]"
-    """The result of an arrange operation."""
+DockArrangeResult: TypeAlias = "tuple[list[WidgetPlacement], set[Widget], Spacing]"
-
-    placements: list[WidgetPlacement]
-    widgets: set[Widget]
-    spacing: Spacing = Spacing()
 
 
 class WidgetPlacement(NamedTuple):
@@ -93,6 +89,6 @@ class Layout(ABC):
         if not widget.displayed_children:
             height = container.height
         else:
-            placements, widgets = widget._arrange(Size(width, container.height))
+            placements, *_ = widget._arrange(Size(width, container.height))
             height = max(placement.region.bottom for placement in placements)
         return height

src/textual/_styles_cache.py

@@ -246,7 +246,9 @@ class StylesCache:
         line: Iterable[Segment]
         # Draw top or bottom borders (A)
         if (border_top and y == 0) or (border_bottom and y == height - 1):
-            border_color = border_top_color if y == 0 else border_bottom_color
+            border_color = background + (
+                border_top_color if y == 0 else border_bottom_color
+            )
             box_segments = get_box(
                 border_top if y == 0 else border_bottom,
                 inner,
@@ -290,9 +292,9 @@ class StylesCache:
 
             if border_left or border_right:
                 # Add left / right border
-                left_style = from_color(border_left_color.rich_color)
+                left_style = from_color((background + border_left_color).rich_color)
                 left = get_box(border_left, inner, outer, left_style)[1][0]
-                right_style = from_color(border_right_color.rich_color)
+                right_style = from_color((background + border_right_color).rich_color)
                 right = get_box(border_right, inner, outer, right_style)[1][2]
 
                 if border_left and border_right:
@@ -321,9 +323,9 @@ class StylesCache:
 
         elif outline_left or outline_right:
             # Lines in side outline
-            left_style = from_color(outline_left_color.rich_color)
+            left_style = from_color((background + outline_left_color).rich_color)
             left = get_box(outline_left, inner, outer, left_style)[1][0]
-            right_style = from_color(outline_right_color.rich_color)
+            right_style = from_color((background + outline_right_color).rich_color)
             right = get_box(outline_right, inner, outer, right_style)[1][2]
             line = line_trim(list(line), outline_left != "", outline_right != "")
             if outline_left and outline_right:

src/textual/css/_style_properties.py

@@ -802,8 +802,9 @@ class NameListProperty:
 class ColorProperty:
     """Descriptor for getting and setting color properties."""
 
-    def __init__(self, default_color: Color | str) -> None:
+    def __init__(self, default_color: Color | str, background: bool = False) -> None:
         self._default_color = Color.parse(default_color)
+        self._is_background = background
 
     def __set_name__(self, owner: StylesBase, name: str) -> None:
         self.name = name
@@ -837,10 +838,10 @@ class ColorProperty:
         _rich_traceback_omit = True
         if color is None:
             if obj.clear_rule(self.name):
-                obj.refresh(children=True)
+                obj.refresh(children=self._is_background)
         elif isinstance(color, Color):
             if obj.set_rule(self.name, color):
-                obj.refresh(children=True)
+                obj.refresh(children=self._is_background)
         elif isinstance(color, str):
             alpha = 1.0
             parsed_color = Color(255, 255, 255)
@@ -862,7 +863,7 @@ class ColorProperty:
                     )
             parsed_color = parsed_color.with_alpha(alpha)
             if obj.set_rule(self.name, parsed_color):
-                obj.refresh(children=True)
+                obj.refresh(children=self._is_background)
         else:
             raise StyleValueError(f"Invalid color value {color}")
 

src/textual/css/styles.py

@@ -185,7 +185,7 @@ class StylesBase(ABC):
     layout = LayoutProperty()
 
     color = ColorProperty(Color(255, 255, 255))
-    background = ColorProperty(Color(0, 0, 0, 0))
+    background = ColorProperty(Color(0, 0, 0, 0), background=True)
     text_style = StyleFlagsProperty()
 
     opacity = FractionalProperty()
@@ -437,6 +437,15 @@ class StylesBase(ABC):
         return offset_y
 
     def align_size(self, child: tuple[int, int], parent: tuple[int, int]) -> Offset:
+        """Align a size according to alignment rules.
+
+        Args:
+            child (tuple[int, int]): The size of the child (width, height)
+            parent (tuple[int, int]): The size of the parent (width, height)
+
+        Returns:
+            Offset: Offset required to align the child.
+        """
         width, height = child
         parent_width, parent_height = parent
         return Offset(

src/textual/css/stylesheet.py

@@ -304,6 +304,8 @@ class Stylesheet:
             animate (bool, optional): Animate changed rules. Defaults to ``False``.
         """
 
+        print(node)
+
         # Dictionary of rule attribute names e.g. "text_background" to list of tuples.
         # The tuples contain the rule specificity, and the value for that rule.
         # We can use this to determine, for a given rule, whether we should apply it
@@ -405,7 +407,12 @@ class Stylesheet:
         else:
             # Not animated, so we apply the rules directly
             get_rule = rules.get
+            from ..screen import Screen
+
             for key in modified_rule_keys:
+                if isinstance(node, Screen):
+
+                    print(node, key, get_rule(key))
                 setattr(base_styles, key, get_rule(key))
 
         node.post_message_no_wait(messages.StylesUpdated(sender=node))

src/textual/layouts/vertical.py

@@ -60,4 +60,4 @@ class VerticalLayout(Layout):
         total_region = Region(0, 0, size.width, int(y))
         add_placement(WidgetPlacement(total_region, None, 0))
 
-        return ArrangeResult(placements, set(children))
+        return placements, set(children)

src/textual/screen.py

@@ -117,7 +117,11 @@ class Screen(Widget):
             self._refresh_layout()
             self._layout_required = False
             self._dirty_widgets.clear()
-        elif self._dirty_widgets:
+        if self._repaint_required:
+            self._dirty_widgets.add(self)
+            self._repaint_required = False
+
+        if self._dirty_widgets:
             self.update_timer.resume()
 
     def _on_update(self) -> None: