refreshing invisible widgets is a no-op

CHANGELOG.md

@@ -7,8 +7,13 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Unreleased
 
+### Fixed
+
+- Fixed issue with screen not updating when auto_refresh was enabled https://github.com/Textualize/textual/pull/5063
+
 ### Added
 
+- Added `DOMNode.is_on_screen` property https://github.com/Textualize/textual/pull/5063
 - Added support for keymaps (user configurable key bindings) https://github.com/Textualize/textual/pull/5038
 
 ## [0.81.0] - 2024-09-25

src/textual/_compositor.py

@@ -311,9 +311,6 @@ def __init__(self) -> None:
  # Mapping of line numbers on to lists of widget and regions
  self._layers_visible: list[list[tuple[Widget, Region, Region]]] | None = None
 
- # New widgets added between updates
- self._new_widgets: set[Widget] = set()
-
  def clear(self) -> None:
  """Remove all references to widgets (used when the screen closes)."""
  self._full_map.clear()
@@ -392,8 +389,7 @@ def reflow(self, parent: Widget, size: Size) -> ReflowResult:
  new_widgets = map.keys()
 
  # Newly visible widgets
- shown_widgets = (new_widgets - old_widgets) | self._new_widgets
- self._new_widgets.clear()
+ shown_widgets = new_widgets - old_widgets
 
  # Newly hidden widgets
  hidden_widgets = self.widgets - widgets
@@ -490,7 +486,6 @@ def full_map(self) -> CompositorMap:
  self._full_map_invalidated = False
  map, _widgets = self._arrange_root(self.root, self.size, visible_only=False)
  # Update any widgets which became visible in the interim
- self._new_widgets.update(map.keys() - self._full_map.keys())
  self._full_map = map
  self._visible_widgets = None
  self._visible_map = None
@@ -803,6 +798,22 @@ def layers_visible(self) -> list[list[tuple[Widget, Region, Region]]]:
  self._layers_visible = layers_visible
  return self._layers_visible
 
+ def __contains__(self, widget: Widget) -> bool:
+ """Check if the widget was included in the last update.
+
+ Args:
+ widget: A widget.
+
+ Returns:
+ `True` if the widget was in the last refresh, or `False` if it wasn't.
+ """
+ # Try to avoid a recalculation of full_map if possible.
+ return (
+ widget in self.widgets
+ or (self._visible_map is not None and widget in self._visible_map)
+ or widget in self.full_map
+ )
+
  def get_offset(self, widget: Widget) -> Offset:
  """Get the offset of a widget.
 

src/textual/dom.py

@@ -489,6 +489,11 @@ def is_modal(self) -> bool:
  """Is the node a modal?"""
  return False
 
+ @property
+ def is_on_screen(self) -> bool:
+ """Check if the node was displayed in the last screen update."""
+ return False
+
  def automatic_refresh(self) -> None:
  """Perform an automatic refresh.
 
@@ -497,7 +502,7 @@ def automatic_refresh(self) -> None:
  during an automatic refresh.
 
  """
- if self.display and self.visible:
+ if self.is_on_screen:
  self.refresh()
 
  def __init_subclass__(

src/textual/screen.py

@@ -147,6 +147,7 @@ class Screen(Generic[ScreenResultType], Widget):
 
  DEFAULT_CSS = """
  Screen {
+
  layout: vertical;
  overflow-y: auto;
  background: $surface; 
@@ -162,11 +163,11 @@ class Screen(Generic[ScreenResultType], Widget):
  background: ansi_default;
  color: ansi_default;
 
- &.-screen-suspended {
+ &.-screen-suspended { 
+ text-style: dim;
  ScrollBar {
  text-style: not dim;
  }
- text-style: dim;
  }
  }
  }
@@ -1136,8 +1137,9 @@ async def _on_update(self, message: messages.Update) -> None:
  widget = message.widget
  assert isinstance(widget, Widget)
 
- self._dirty_widgets.add(widget)
- self.check_idle()
+ if self in self._compositor:
+ self._dirty_widgets.add(widget)
+ self.check_idle()
 
  async def _on_layout(self, message: messages.Layout) -> None:
  message.stop()

src/textual/widget.py

@@ -1927,6 +1927,15 @@ def _has_relative_children_height(self) -> bool:
  return True
  return False
 
+ @property
+ def is_on_screen(self) -> bool:
+ """Check if the node was displayed in the last screen update."""
+ try:
+ self.screen.find_widget(self)
+ except (NoScreen, errors.NoWidget):
+ return False
+ return True
+
  def animate(
  self,
  attribute: str,

tests/snapshot_tests/test_snapshots.py

@@ -23,6 +23,7 @@
  Footer,
  Log,
  OptionList,
+ Placeholder,
  SelectionList,
 )
 from textual.widgets import ProgressBar, Label, Switch
@@ -2098,3 +2099,38 @@ def action_toggle_console(self) -> None:
 
  app = MRE()
  assert snap_compare(app, press=["space", "space", "z"])
+
+
+def test_updates_with_auto_refresh(snap_compare):
+ """Regression test for https://github.com/Textualize/textual/issues/5056
+
+ After hiding and unhiding the RichLog, you should be able to see 1.5 fully rendered placeholder widgets.
+ Prior to this fix, the bottom portion of the screen did not 
+ refresh after the RichLog was hidden/unhidden while in the presence of the auto-refreshing ProgressBar widget.
+ """
+
+ class MRE(App):
+ BINDINGS = [
+ ("z", "toggle_widget('RichLog')", "Console"),
+ ]
+ CSS = """
+ Placeholder { height: 15; }
+ RichLog { height: 6; }
+ .hidden { display: none; }
+ """
+
+ def compose(self):
+ with VerticalScroll():
+ for i in range(10):
+ yield Placeholder()
+ yield ProgressBar(classes="hidden")
+ yield RichLog(classes="hidden")
+
+ def on_ready(self) -> None:
+ self.query_one(RichLog).write("\n".join(f"line #{i}" for i in range(5)))
+
+ def action_toggle_widget(self, widget_type: str) -> None:
+ self.query_one(widget_type).toggle_class("hidden")
+
+ app = MRE()
+ assert snap_compare(app, press=["z", "z"])