diff --git a/src/styles/components.rs b/src/styles/components.rs
index 8decc34..d8dab6d 100644
--- a/src/styles/components.rs
+++ b/src/styles/components.rs
@@ -145,7 +145,15 @@ define_components! {
         /// The [`Color`] to use when rendering text in a more subdued tone.
         TextColorVariant(Color, "text_color_variant", .surface.on_color_variant)
         /// A [`Color`] to be used as a highlight color.
-        HighlightColor(Color,"highlight_color",.primary.color.with_alpha(128))
+        HighlightColor(Color,"highlight_color", .primary.color.with_alpha(128))
+        /// The primary color from the current theme.
+        PrimaryColor(Color, "primary_color", .primary.color)
+        /// The secondary color from the current theme.
+        SecondaryColor(Color, "secondary_color", .secondary.color)
+        /// The tertiary color from the current theme.
+        TertiaryColor(Color, "tertiary_color", .tertiary.color)
+        /// The error color from the current theme.
+        ErrorColor(Color, "error_color", .error.color)
         /// Intrinsic, uniform padding for a widget.
         ///
         /// This component is opt-in and does not automatically work for all widgets.
diff --git a/src/widget.rs b/src/widget.rs
index fdb45cb..5e9dbb4 100644
--- a/src/widget.rs
+++ b/src/widget.rs
@@ -2078,6 +2078,12 @@ impl WidgetId {
         static COUNTER: AtomicU64 = AtomicU64::new(0);
         Self(COUNTER.fetch_add(1, atomic::Ordering::Acquire))
     }
+
+    /// Finds this widget mounted in this window, if present.
+    #[must_use]
+    pub fn find_in(self, context: &WidgetContext<'_, '_>) -> Option<ManagedWidget> {
+        context.widget().tree.widget(self)
+    }
 }
 
 /// A [`WidgetId`] that has not been assigned to a [`WidgetInstance`].
diff --git a/src/widgets.rs b/src/widgets.rs
index d0d1947..09c6057 100644
--- a/src/widgets.rs
+++ b/src/widgets.rs
@@ -16,7 +16,7 @@ pub mod label;
 pub mod layers;
 mod mode_switch;
 pub mod progress;
-mod radio;
+pub mod radio;
 mod resize;
 pub mod scroll;
 pub mod select;
@@ -27,7 +27,7 @@ mod style;
 mod switcher;
 mod themed;
 mod tilemap;
-mod validated;
+pub mod validated;
 pub mod wrap;
 
 pub use align::Align;
diff --git a/src/widgets/checkbox.rs b/src/widgets/checkbox.rs
index a2b7981..a66d0d7 100644
--- a/src/widgets/checkbox.rs
+++ b/src/widgets/checkbox.rs
@@ -9,6 +9,7 @@ use kludgine::shapes::{PathBuilder, Shape, StrokeOptions};
 
 use crate::context::{GraphicsContext, LayoutContext};
 use crate::styles::components::{LineHeight, OutlineColor, TextColor, WidgetAccentColor};
+use crate::styles::Dimension;
 use crate::value::{Dynamic, DynamicReader, IntoDynamic, IntoValue, Value};
 use crate::widget::{MakeWidget, MakeWidgetWithId, Widget, WidgetInstance};
 use crate::widgets::button::ButtonKind;
@@ -241,7 +242,7 @@ impl Widget for CheckboxOrnament {
         _available_space: Size<ConstraintLimit>,
         context: &mut LayoutContext<'_, '_, '_, '_, '_>,
     ) -> Size<kludgine::figures::units::UPx> {
-        let checkbox_size = context.get(&LineHeight).into_upx(context.gfx.scale()); // TODO create a component?
+        let checkbox_size = context.get(&CheckboxSize).into_upx(context.gfx.scale());
         Size::squared(checkbox_size)
     }
 }
@@ -255,3 +256,10 @@ pub trait Checkable: IntoDynamic<CheckboxState> + Sized {
 }
 
 impl<T> Checkable for T where T: IntoDynamic<CheckboxState> {}
+
+define_components! {
+    Checkbox {
+        /// The size to render a [`Checkbox`] indicator.
+        CheckboxSize(Dimension, "size", @LineHeight)
+    }
+}
diff --git a/src/widgets/container.rs b/src/widgets/container.rs
index 0777a0d..b8c536d 100644
--- a/src/widgets/container.rs
+++ b/src/widgets/container.rs
@@ -308,8 +308,6 @@ impl Widget for Container {
         &mut self,
         context: &mut EventContext<'_, '_>,
     ) -> Option<(RootBehavior, WidgetInstance)> {
-        // TODO adjust for shadow, but we need to potentially merge multiple
-        // dimensions into one.
         let mut padding = self
             .padding
             .as_ref()
diff --git a/src/widgets/grid.rs b/src/widgets/grid.rs
index ef4dcdd..730c27e 100644
--- a/src/widgets/grid.rs
+++ b/src/widgets/grid.rs
@@ -659,11 +659,9 @@ mod tests {
         let mut offset = UPx::ZERO;
         for ((index, &child), &expected) in flex.iter().enumerate().zip(expected) {
             assert_eq!(
+                child.size, expected,
+                "child {index} measured to {}, expected {expected}",
                 child.size,
-                expected,
-                "child {index} measured to {}, expected {}",
-                child.size,
-                expected // TODO Display for UPx
             );
             assert_eq!(child.offset, offset);
             offset += child.size;
diff --git a/src/widgets/layers.rs b/src/widgets/layers.rs
index 91bc296..fd1a8f9 100644
--- a/src/widgets/layers.rs
+++ b/src/widgets/layers.rs
@@ -332,8 +332,8 @@ impl OverlayState {
             .overlays
             .get_by_index(0)
             .and_then(|overlay| overlay.relative_to)
-            .and_then(|relative_to| context.widget.for_other(&relative_to))
-            .and_then(|c| c.widget().last_layout())
+            .and_then(|relative_to| relative_to.find_in(context))
+            .and_then(|w| w.last_layout())
         {
             if !relative_to.contains(location) {
                 return true;
@@ -381,13 +381,8 @@ impl OverlayState {
         context: &mut LayoutContext<'_, '_, '_, '_, '_>,
         relative_to: WidgetId,
     ) -> Option<Rect<Px>> {
-        // TODO resolving a widgetid should probably be easier
         let direction = self.overlays[index].direction;
-        let relative_to = context
-            .widget
-            .for_other(&relative_to)
-            .map(|c| c.widget().clone())?
-            .last_layout()?;
+        let relative_to = relative_to.find_in(context)?.last_layout()?;
         let relative_to_unsigned = relative_to.into_unsigned();
 
         let constraints = match direction {
@@ -485,8 +480,8 @@ impl OverlayState {
         if checking_index != 0 {
             if let Some(relative_to) = self.overlays[0]
                 .relative_to
-                .and_then(|relative_to| context.widget.for_other(&relative_to))
-                .and_then(|c| c.widget().last_layout())
+                .and_then(|relative_to| relative_to.find_in(context))
+                .and_then(|w| w.last_layout())
             {
                 if relative_to.intersects(layout) {
                     return true;
diff --git a/src/widgets/radio.rs b/src/widgets/radio.rs
index 120251f..9a49d3e 100644
--- a/src/widgets/radio.rs
+++ b/src/widgets/radio.rs
@@ -9,6 +9,7 @@ use kludgine::DrawableExt;
 
 use crate::context::{GraphicsContext, LayoutContext};
 use crate::styles::components::{LineHeight, OutlineColor, WidgetAccentColor};
+use crate::styles::Dimension;
 use crate::value::{Dynamic, DynamicReader, IntoDynamic, IntoValue, Value};
 use crate::widget::{MakeWidget, MakeWidgetWithId, Widget, WidgetInstance};
 use crate::widgets::button::ButtonKind;
@@ -121,7 +122,14 @@ where
         _available_space: Size<ConstraintLimit>,
         context: &mut LayoutContext<'_, '_, '_, '_, '_>,
     ) -> Size<kludgine::figures::units::UPx> {
-        let radio_size = context.get(&LineHeight).into_upx(context.gfx.scale()); // TODO create a component? Same as checkbox
+        let radio_size = context.get(&RadioSize).into_upx(context.gfx.scale());
         Size::squared(radio_size)
     }
 }
+
+define_components! {
+    Radio {
+        /// The size to render a [`Radio`] indicator.
+        RadioSize(Dimension, "size", @LineHeight)
+    }
+}
diff --git a/src/widgets/validated.rs b/src/widgets/validated.rs
index 34dc976..1139fcc 100644
--- a/src/widgets/validated.rs
+++ b/src/widgets/validated.rs
@@ -1,9 +1,13 @@
+//! A widget that displays the result of validation.
+
 use std::fmt::Debug;
 
-use kludgine::figures::units::Lp;
 use kludgine::Color;
 
-use crate::styles::components::{LineHeight, OutlineColor, TextColor, TextSize};
+use crate::styles::components::{
+    ErrorColor, LineHeight, LineHeight2, OutlineColor, TextColor, TextSize, TextSize2,
+};
+use crate::styles::Dimension;
 use crate::value::{Dynamic, IntoDynamic, IntoValue, MapEach, Validation, Value};
 use crate::widget::{MakeWidget, MakeWidgetWithId, WidgetInstance, WidgetRef, WrapperWidget};
 
@@ -71,9 +75,8 @@ impl MakeWidgetWithId for Validated {
                     .and(
                         message
                             .with(&TextColor, color)
-                            // TODO these should be components
-                            .with(&TextSize, Lp::points(9))
-                            .with(&LineHeight, Lp::points(13))
+                            .with_dynamic(&TextSize, ValidatedTextSize)
+                            .with_dynamic(&LineHeight, ValidatedLineHeight)
                             .align_left(),
                     )
                     .into_rows(),
@@ -101,8 +104,20 @@ impl WrapperWidget for ValidatedWidget {
         &mut self,
         context: &mut crate::context::GraphicsContext<'_, '_, '_, '_, '_>,
     ) {
-        // TODO move these to components.
-        self.error_color.set(context.theme().error.color);
-        self.default_color.set(context.theme().surface.outline);
+        self.error_color.set(context.get(&InvalidTextColor));
+        self.default_color.set(context.get(&HintTextColor));
+    }
+}
+
+define_components! {
+    Validated {
+        /// The color of the hint text.
+        HintTextColor(Color, "hint_color", @OutlineColor)
+        /// The color of invalid text.
+        InvalidTextColor(Color, "invalid_color", @ErrorColor)
+        /// The text size for the validation message in a [`Validated`] widget.
+        ValidatedTextSize(Dimension, "text_size", @TextSize2)
+        /// The line hgiht for the validation message in a [`Validated`] widget.
+        ValidatedLineHeight(Dimension, "line_height", @LineHeight2)
     }
 }
diff --git a/src/widgets/wrap.rs b/src/widgets/wrap.rs
index b536ce8..ff05378 100644
--- a/src/widgets/wrap.rs
+++ b/src/widgets/wrap.rs
@@ -228,8 +228,6 @@ pub enum VerticalAlign {
     Middle,
 
     /// Align towards the bottom.
-    // TODO the default should be `Baseline`, but that requires a refactor for
-    // layout() to return something other than a Size.
     #[default]
     Bottom,
 }
diff --git a/src/window.rs b/src/window.rs
index c87929e..803eacc 100644
--- a/src/window.rs
+++ b/src/window.rs
@@ -661,9 +661,7 @@ where
         if let Some(theme) = &mut self.theme {
             if theme.has_updated() {
                 self.current_theme = theme.get();
-                // TODO invalidate everything, but right now we don't have much
-                // cached. Maybe widgets should be told the theme has changed in
-                // case some things like images have been cached.
+                self.root.invalidate();
             }
         }