alignment fix

sandbox/will/screens.py

@@ -8,7 +8,7 @@ class ModalScreen(Screen):
         yield Footer()
 
     def on_screen_resume(self):
-        self.query("*").refresh()
+        self.query_one(Pretty).update(self.app.screen_stack)
 
 
 class NewScreen(Screen):
@@ -25,14 +25,19 @@ class ScreenApp(App):
     ScreenApp Screen {
         background: #111144;
         color: white;
+     
+       
     }
     ScreenApp ModalScreen {
         background: #114411;
         color: white;
+        
+      
     }
-    ScreenApp Static {
-        height: 100%;        
+    ScreenApp Pretty {        
+        height: auto;        
         content-align: center middle;
+        background: white 20%;
     }
     """
 

src/textual/_border.py

@@ -263,6 +263,8 @@ class Border:
                 else:
                     render_options = options.update_width(width)
 
+        print("LINES", self.renderable)
+        print(render_options)
         lines = console.render_lines(self.renderable, render_options)
 
         if self.outline:

src/textual/_segment_tools.py

@@ -10,6 +10,9 @@ from rich.segment import Segment
 from rich.style import Style
 
 from ._cells import cell_len
+from ._types import Lines
+from .css.types import AlignHorizontal, AlignVertical
+from .geometry import Size
 
 
 def line_crop(
@@ -124,3 +127,73 @@ def line_pad(
             Segment(" " * pad_right, style),
         ]
     return list(segments)
+
+
+def align_lines(
+    lines: Lines,
+    style: Style,
+    size: Size,
+    horizontal: AlignHorizontal,
+    vertical: AlignVertical,
+) -> Iterable[list[Segment]]:
+    """Align lines.
+
+    Args:
+        lines (Lines): A list of lines.
+        style (Style): Background style.
+        size (Size): Size of container.
+        horizontal (AlignHorizontal): Horizontal alignment.
+        vertical (AlignVertical): Vertical alignment
+
+    Returns:
+        Iterable[list[Segment]]: Aligned lines.
+
+    """
+
+    width, height = size
+    shape_width, shape_height = Segment.get_shape(lines)
+
+    print("len lines", len(lines))
+    print(width, height)
+    print(shape_width, shape_height)
+
+    def blank_lines(count: int) -> Lines:
+        return [[Segment(" " * width, style)]] * count
+
+    top_blank_lines = bottom_blank_lines = 0
+    vertical_excess_space = max(0, height - shape_height)
+    print("VERTICAL EXCESS", vertical_excess_space)
+    print("height", height, "shape height", shape_height)
+    if vertical == "top":
+        bottom_blank_lines = vertical_excess_space
+    elif vertical == "middle":
+        top_blank_lines = vertical_excess_space // 2
+        bottom_blank_lines = height - top_blank_lines
+    elif vertical == "bottom":
+        top_blank_lines = vertical_excess_space
+
+    print(top_blank_lines)
+    yield from blank_lines(top_blank_lines)
+
+    horizontal_excess_space = max(0, width - shape_width)
+
+    adjust_line_length = Segment.adjust_line_length
+    if horizontal == "left":
+        for line in lines:
+            yield adjust_line_length(line, width, style, pad=True)
+
+    elif horizontal == "center":
+        left_space = horizontal_excess_space // 2
+        for line in lines:
+            yield [
+                Segment(" " * left_space, style),
+                *adjust_line_length(line, width - left_space, style, pad=True),
+            ]
+
+    elif horizontal == "right":
+        get_line_length = Segment.get_line_length
+        for line in lines:
+            left_space = width - get_line_length(line)
+            yield [*line, Segment(" " * left_space, style)]
+
+    yield from blank_lines(bottom_blank_lines)

src/textual/app.py

@@ -668,7 +668,7 @@ class App(Generic[ReturnType], DOMNode):
         self.screen.post_message_no_wait(events.ScreenResume(self))
         return current_screen
 
-    def pop_screen(self) -> Screen:
+    def pop_screen(self, remove: bool | None = None) -> Screen:
         """Pop the current screen from the stack, and switch to the previous screen.
 
         Returns:
@@ -680,10 +680,25 @@ class App(Generic[ReturnType], DOMNode):
                 "Can't pop screen; there must be at least one screen on the stack"
             )
         screen = screen_stack.pop()
-        screen.remove()
         screen.post_message_no_wait(events.ScreenSuspend(self))
         self.screen._screen_resized(self.size)
         self.screen.post_message_no_wait(events.ScreenResume(self))
+
+        if remove is None:
+            if screen not in self.SCREENS.values():
+                screen.remove()
+            else:
+                screen.detach()
+        else:
+            if remove:
+                if screen in self.SCREENS.values():
+                    raise ScreenStackError("Can't remove screen set in App.SCREENS")
+                screen.remove()
+            else:
+                screen.detach()
+
+        print(self._registry)
+
         return screen
 
     def set_focus(self, widget: Widget | None) -> None:
@@ -692,7 +707,6 @@ class App(Generic[ReturnType], DOMNode):
         Args:
             widget (Widget): [description]
         """
-        self.log("set_focus", widget=widget)
         if widget == self.focused:
             # Widget is already focused
             return
@@ -910,7 +924,7 @@ class App(Generic[ReturnType], DOMNode):
         if child not in self._registry:
             parent.children._append(child)
             self._registry.add(child)
-            child.set_parent(parent)
+            child._attach(parent)
             child.on_register(self)
             child.start_messages()
             return True
@@ -948,10 +962,11 @@ class App(Generic[ReturnType], DOMNode):
         """Unregister a widget.
 
         Args:
-            widget (Widget): _description_
+            widget (Widget): A Widget to unregister
         """
         if isinstance(widget._parent, Widget):
             widget._parent.children._remove(widget)
+            widget._attach(None)
         self._registry.discard(widget)
 
     async def _disconnect_devtools(self):
@@ -964,7 +979,7 @@ class App(Generic[ReturnType], DOMNode):
             parent (Widget): The parent of the Widget.
             widget (Widget): The Widget to start.
         """
-        widget.set_parent(parent)
+        widget._attach(parent)
         widget.start_messages()
         widget.post_message_no_wait(events.Mount(sender=parent))
 

src/textual/css/stylesheet.py

@@ -355,7 +355,7 @@ class Stylesheet:
         node._component_styles.clear()
         for component in node.COMPONENT_CLASSES:
             virtual_node = DOMNode(classes=component)
-            virtual_node.set_parent(node)
+            virtual_node._attach(node)
             self.apply(virtual_node, animate=False)
             node._component_styles[component] = virtual_node.styles
 

src/textual/dom.py

@@ -445,7 +445,10 @@ class DOMNode(MessagePump):
     def detach(self) -> None:
         if self._parent and isinstance(self._parent, DOMNode):
             self._parent.children._remove(self)
-            self.set_parent(None)
+            print(self.parent.children)
+            self._detach()
+            print("DETATCH", self)
+            print(self.app._registry)
 
     def get_pseudo_classes(self) -> Iterable[str]:
         """Get any pseudo classes applicable to this Node, e.g. hover, focus.
@@ -472,7 +475,7 @@ class DOMNode(MessagePump):
             node (DOMNode): A DOM node.
         """
         self.children._append(node)
-        node.set_parent(self)
+        node._attach(self)
 
     def add_children(self, *nodes: Widget, **named_nodes: Widget) -> None:
         """Add multiple children to this node.
@@ -483,10 +486,10 @@ class DOMNode(MessagePump):
         """
         _append = self.children._append
         for node in nodes:
-            node.set_parent(self)
+            node._attach(self)
             _append(node)
         for node_id, node in named_nodes.items():
-            node.set_parent(self)
+            node._attach(self)
             _append(node)
             node.id = node_id
 

src/textual/message_pump.py

@@ -122,9 +122,18 @@ class MessagePump(metaclass=MessagePumpMeta):
     def log(self, *args, **kwargs) -> None:
         return self.app.log(*args, **kwargs, _textual_calling_frame=inspect.stack()[1])
 
-    def set_parent(self, parent: MessagePump | None) -> None:
+    def _attach(self, parent: MessagePump) -> None:
+        """Set the parent, and therefore attach this node to the tree.
+
+        Args:
+            parent (MessagePump): Parent node.
+        """
         self._parent = parent
 
+    def _detach(self) -> None:
+        """Unset the parent, removing it from the tree."""
+        self._parent = None
+
     def check_message_enabled(self, message: Message) -> bool:
         return type(message) not in self._disabled_messages
 

src/textual/renderables/align.py

@@ -0,0 +1,48 @@
+from __future__ import annotations
+
+from rich.console import Console, ConsoleOptions, RenderableType, RenderResult
+from rich.measure import Measurement
+from rich.segment import Segment
+from rich.style import Style
+
+from ..geometry import Size
+from ..css.types import AlignHorizontal, AlignVertical
+from .._segment_tools import align_lines
+
+
+class Align:
+    def __init__(
+        self,
+        renderable: RenderableType,
+        size: Size,
+        style: Style,
+        horizontal: AlignHorizontal,
+        vertical: AlignVertical,
+    ) -> None:
+        self.renderable = renderable
+        self.size = size
+        self.style = style
+        self.horizontal = horizontal
+        self.vertical = vertical
+
+    def __rich_console__(
+        self, console: Console, options: ConsoleOptions
+    ) -> RenderResult:
+        lines = console.render_lines(self.renderable, options, pad=False)
+
+        new_line = Segment.line()
+        for line in align_lines(
+            lines,
+            self.style,
+            self.size,
+            self.horizontal,
+            self.vertical,
+        ):
+            yield from line
+            yield new_line
+
+    def __rich_measure__(
+        self, console: "Console", options: "ConsoleOptions"
+    ) -> Measurement:
+        width, _ = self.size
+        return Measurement(width, width)

src/textual/screen.py

@@ -33,7 +33,6 @@ class Screen(Widget):
 
     CSS = """
     Screen {
-
         layout: vertical;
         overflow-y: auto;
     }

src/textual/widget.py

@@ -14,7 +14,7 @@ from typing import (
 )
 
 import rich.repr
-from rich.align import Align
+
 from rich.console import Console, RenderableType
 from rich.measure import Measurement
 from rich.segment import Segment
@@ -27,6 +27,7 @@ from ._animator import BoundAnimator
 from ._arrange import arrange, DockArrangeResult
 from ._context import active_app
 from ._layout import Layout
+from ._segment_tools import align_lines
 from ._styles_cache import StylesCache
 from ._types import Lines
 from .box_model import BoxModel, get_box_model
@@ -35,6 +36,8 @@ from .geometry import Offset, Region, Size, Spacing, clamp
 from .layouts.vertical import VerticalLayout
 from .message import Message
 from .reactive import Reactive, watch
+from .renderables.align import Align
+
 
 if TYPE_CHECKING:
     from .app import App, ComposeResult
@@ -287,6 +290,7 @@ class Widget(DOMNode):
         Returns:
             int: The height of the content.
         """
+
         if self.is_container:
             assert self.layout is not None
             height = (
@@ -306,7 +310,7 @@ class Widget(DOMNode):
 
             renderable = self.render()
             options = self.console.options.update_width(width).update(highlight=False)
-            segments = self.console.render(renderable, options)
+            segments = list(self.console.render(renderable, options))
             # Cheaper than counting the lines returned from render_lines!
             height = sum(text.count("\n") for text, _, _ in segments)
             self._content_height_cache = (cache_key, height)
@@ -989,7 +993,15 @@ class Widget(DOMNode):
         )
         if content_align != ("left", "top"):
             horizontal, vertical = content_align
-            renderable = Align(renderable, horizontal, vertical=vertical)
+            # TODO: This changes the shape of the renderable and breaks alignment
+            # We need custom functionality that doesn't measure the renderable again
+            renderable = Align(
+                renderable,
+                self.size,
+                rich_style,
+                horizontal,
+                vertical,
+            )
 
         return renderable
 
@@ -1030,8 +1042,10 @@ class Widget(DOMNode):
         width, height = self.size
         renderable = self.render()
         renderable = self.post_render(renderable)
-        options = self.console.options.update_dimensions(width, height).update(
-            highlight=False
+        options = (
+            self.console.options.update_width(width)
+            .update(highlight=False)
+            .reset_height()
         )
         lines = self.console.render_lines(renderable, options)
         self._render_cache = RenderCache(self.size, lines)
@@ -1180,9 +1194,9 @@ class Widget(DOMNode):
 
     async def on_remove(self, event: events.Remove) -> None:
         await self.close_messages()
-        self.app._unregister(self)
         assert self.parent
         self.parent.refresh(layout=True)
+        self.app._unregister(self)
 
     def _on_mount(self, event: events.Mount) -> None:
         widgets = list(self.compose())

src/textual/widgets/_pretty.py

@@ -2,10 +2,17 @@ from __future__ import annotations
 
 from typing import Any
 from rich.pretty import Pretty as PrettyRenderable
-from ._static import Static
+
+from ..widget import Widget
 
 
-class Pretty(Static):
+class Pretty(Widget):
+    CSS = """
+    Static {
+        height: auto;
+    }
+    """
+
     def __init__(
         self,
         object: Any,
@@ -14,10 +21,16 @@ class Pretty(Static):
         id: str | None = None,
         classes: str | None = None,
     ) -> None:
-        self._object = object
         super().__init__(
-            PrettyRenderable(self._object),
             name=name,
             id=id,
             classes=classes,
         )
+        self._renderable = PrettyRenderable(object)
+
+    def render(self) -> PrettyRenderable:
+        return self._renderable
+
+    def update(self, object: Any) -> None:
+        self._renderable = PrettyRenderable(object)
+        self.refresh()