Added List widget

CHANGELOG.md

@@ -213,6 +213,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   returns a `plotters::DrawingArea` that can be used to draw any plot that the
   `plotters` crate supports.
 - `Delimiter` is a new widget that is similar to html's `hr` tag.
+- `List` is a new widget that creates lists similar to HTML's `ol` and `ul`
+  tags.
 
 [plotters]: https://github.com/plotters-rs/plotters
 
@@ -233,6 +235,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `Window::new` no longer accepts a `Cushy` parameter. The window now adopts the
   `Cushy` from the application it is opened within.
 - `MakeWidget::into_window()` no longer takes any parameters.
+- `Label<T>` is now generic over a new trait: `DynamicDisplay`. This new trait
+  allows a way to query a `WidgetContext` to resolve the value to display. The
+  trait is automatically implemented for all types that implement `Display`, so
+  this change in practice shouldn't break much code.
 
 ### Changed
 

Cargo.lock

@@ -576,6 +576,7 @@ dependencies = [
  "interner",
  "kempt",
  "kludgine",
+ "nominals",
  "palette",
  "plotters",
  "png",
@@ -1479,6 +1480,12 @@ dependencies = [
  "memoffset",
 ]
 
+[[package]]
+name = "nominals"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8c1ae56aa93d00075cffa92cf1a4f525bfb6664fe70c062cf793b642e352414f"
+
 [[package]]
 name = "nu-ansi-term"
 version = "0.46.0"

Cargo.toml

@@ -44,6 +44,7 @@ pollster = "0.3.0"
 png = "0.17.10"
 image = { version = "0.24.7", features = ["png"] }
 plotters = { version = "0.3.5", default-features = false, optional = true }
+nominals = "0.2.1"
 
 
 # [patch.crates-io]

examples/list.rs

@@ -0,0 +1,28 @@
+use cushy::value::Dynamic;
+use cushy::widget::{MakeWidget, WidgetList};
+use cushy::widgets::list::ListStyle;
+use cushy::Run;
+
+fn main() -> cushy::Result {
+    let current_style: Dynamic<ListStyle> = Dynamic::default();
+    let options = ListStyle::provided()
+        .into_iter()
+        .map(|style| current_style.new_radio(style.clone(), format!("{style:?}")))
+        .collect::<WidgetList>();
+
+    let rows = (1..100).map(|i| i.to_string()).collect::<WidgetList>();
+
+    options
+        .into_rows()
+        .vertical_scroll()
+        .and(
+            rows.into_list()
+                .style(current_style)
+                .vertical_scroll()
+                .expand(),
+        )
+        .into_columns()
+        .expand()
+        .pad()
+        .run()
+}

src/graphics.rs

@@ -81,10 +81,10 @@ impl<'clip, 'gfx, 'pass> Graphics<'clip, 'gfx, 'pass> {
     /// Sets the font family to the first family in `list`.
     pub fn set_available_font_family(&mut self, list: &FontFamilyList) {
         if self.font_state.current_font_family.as_ref() != Some(list) {
-            self.font_state.current_font_family = Some(list.clone());
             if let Some(family) = self.find_available_font_family(list) {
                 self.set_font_family(family);
             }
+            self.font_state.current_font_family = Some(list.clone());
         }
     }
 

src/styles.rs

@@ -25,6 +25,7 @@ use crate::context::{Trackable, WidgetContext};
 use crate::names::Name;
 use crate::utils::Lazy;
 use crate::value::{Dynamic, IntoValue, Source, Value};
+use crate::widgets::input::CowString;
 
 #[macro_use]
 pub mod components;
@@ -410,6 +411,8 @@ pub enum Component {
     FontWeight(Weight),
     /// The style of a font.
     FontStyle(Style),
+    /// A string value.
+    String(CowString),
 
     /// A custom component type.
     Custom(CustomComponent),
@@ -444,6 +447,38 @@ impl Component {
     }
 }
 
+macro_rules! impl_component_from_string {
+    ($type:ty) => {
+        impl From<$type> for Component {
+            fn from(s: $type) -> Self {
+                Self::String(s.into())
+            }
+        }
+    };
+}
+
+impl_component_from_string!(String);
+impl_component_from_string!(CowString);
+impl_component_from_string!(&'_ str);
+
+macro_rules! impl_component_try_from_string {
+    ($type:ty) => {
+        impl TryFrom<Component> for $type {
+            type Error = Component;
+
+            fn try_from(s: Component) -> Result<Self, Self::Error> {
+                match s {
+                    Component::String(s) => Ok(s.into()),
+                    other => Err(other),
+                }
+            }
+        }
+    };
+}
+
+impl_component_try_from_string!(String);
+impl_component_try_from_string!(CowString);
+
 impl From<FamilyOwned> for Component {
     fn from(value: FamilyOwned) -> Self {
         Self::FontFamily(value)
@@ -2548,6 +2583,18 @@ impl From<Vec<FamilyOwned>> for FontFamilyList {
     }
 }
 
+impl IntoValue<FontFamilyList> for FamilyOwned {
+    fn into_value(self) -> Value<FontFamilyList> {
+        FontFamilyList::from(self).into_value()
+    }
+}
+
+impl IntoValue<FontFamilyList> for Vec<FamilyOwned> {
+    fn into_value(self) -> Value<FontFamilyList> {
+        FontFamilyList::from(self).into_value()
+    }
+}
+
 impl From<FontFamilyList> for Component {
     fn from(list: FontFamilyList) -> Self {
         Component::custom(list)

src/styles/components.rs

@@ -39,7 +39,7 @@ use crate::styles::{Dimension, FocusableWidgets, FontFamilyList, VisualOrder};
 /// ```
 #[macro_export]
 macro_rules! define_components {
-    ($($widget:ident { $($(#$doc:tt)* $component:ident($type:ty, $name:expr, $($default:tt)*))* })*) => {$($(
+    ($($widget:ident { $($(#$doc:tt)* $component:ident($type:ty, $name:expr $(, $($default:tt)*)?))* })*) => {$($(
         $(#$doc)*
         #[derive(Clone, Copy, Eq, PartialEq, Debug)]
         pub struct $component;
@@ -60,7 +60,7 @@ macro_rules! define_components {
             impl ComponentDefinition for $component {
                 type ComponentType = $type;
 
-                define_components!($type, $($default)*);
+                define_components!($type, $($($default)*)?);
             }
         };
 
@@ -84,7 +84,10 @@ macro_rules! define_components {
             ])
         });
     };
-    ($type:ty, $($expr:tt)*) => {
+    ($type:ty, ) => {
+        define_components!($type, |_context| <$type>::default());
+    };
+    ($type:ty, $($expr:tt)+) => {
         define_components!($type, |_context| $($expr)*);
     };
 }

src/value.rs

@@ -1122,7 +1122,7 @@ impl<T> Dynamic<T> {
         // Technically this trait bound isn't necessary, but it prevents trying
         // to call new_radio on unsupported types. The MakeWidget/Widget
         // implementations require these bounds (and more).
-        T: Clone + Eq,
+        T: Clone + PartialEq,
     {
         Radio::new(widget_value, self.clone(), label)
     }
@@ -1137,7 +1137,7 @@ impl<T> Dynamic<T> {
         // Technically this trait bound isn't necessary, but it prevents trying
         // to call new_select on unsupported types. The MakeWidget/Widget
         // implementations require these bounds (and more).
-        T: Clone + Eq,
+        T: Clone + PartialEq,
     {
         Select::new(widget_value, self.clone(), label)
     }

src/widgets/input.rs

@@ -1385,6 +1385,15 @@ where
     }
 }
 
+impl From<CowString> for String {
+    fn from(s: CowString) -> Self {
+        match Arc::try_unwrap(s.0) {
+            Ok(s) => s,
+            Err(arc) => (*arc).clone(),
+        }
+    }
+}
+
 /// A cheap-to-clone, copy-on-write [`String`] type that masks its contents in
 /// [`Debug`] and [`InputStorage`] implementations.
 ///

src/widgets/label.rs

@@ -1,6 +1,6 @@
 //! A read-only text widget.
 
-use std::fmt::Write;
+use std::fmt::{Display, Write};
 
 use figures::units::{Px, UPx};
 use figures::{Point, Round, Size};
@@ -8,7 +8,7 @@ use kludgine::text::{MeasuredText, Text, TextOrigin};
 use kludgine::{CanRenderTo, Color, DrawableExt};
 
 use super::input::CowString;
-use crate::context::{GraphicsContext, LayoutContext, Trackable};
+use crate::context::{GraphicsContext, LayoutContext, Trackable, WidgetContext};
 use crate::styles::components::TextColor;
 use crate::value::{Dynamic, Generation, IntoReadOnly, ReadOnly, Value};
 use crate::widget::{Widget, WidgetInstance};
@@ -26,7 +26,7 @@ pub struct Label<T> {
 
 impl<T> Label<T>
 where
-    T: std::fmt::Debug + std::fmt::Display + Send + 'static,
+    T: std::fmt::Debug + DynamicDisplay + Send + 'static,
 {
     /// Returns a new label that displays `text`.
     pub fn new(text: impl IntoReadOnly<T>) -> Self {
@@ -54,7 +54,7 @@ where
                 context.apply_current_font_settings();
                 let measured = self.display.map(|text| {
                     self.displayed.clear();
-                    if let Err(err) = write!(&mut self.displayed, "{text}") {
+                    if let Err(err) = write!(&mut self.displayed, "{}", text.as_display(context)) {
                         tracing::error!("Error invoking Display: {err}");
                     }
                     context
@@ -75,7 +75,7 @@ where
 
 impl<T> Widget for Label<T>
 where
-    T: std::fmt::Debug + std::fmt::Display + Send + 'static,
+    T: std::fmt::Debug + DynamicDisplay + Send + 'static,
 {
     fn redraw(&mut self, context: &mut GraphicsContext<'_, '_, '_, '_>) {
         self.display.invalidate_when_changed(context);
@@ -132,3 +132,46 @@ impl_make_widget!(
     Value<String> => String,
     ReadOnly<String> => String
 );
+
+/// A context-aware [`Display`] implementation.
+///
+/// This trait is automatically implemented for all types that implement
+/// [`Display`].
+pub trait DynamicDisplay {
+    /// Format `self` with any needed information from `context`.
+    fn fmt(&self, context: &WidgetContext<'_>, f: &mut std::fmt::Formatter<'_>)
+        -> std::fmt::Result;
+
+    /// Returns a type that implements [`Display`].
+    fn as_display<'display, 'ctx>(
+        &'display self,
+        context: &'display WidgetContext<'ctx>,
+    ) -> DynamicDisplayer<'display, 'ctx>
+    where
+        Self: Sized,
+    {
+        DynamicDisplayer(self, context)
+    }
+}
+
+impl<T> DynamicDisplay for T
+where
+    T: Display,
+{
+    fn fmt(
+        &self,
+        _context: &WidgetContext<'_>,
+        f: &mut std::fmt::Formatter<'_>,
+    ) -> std::fmt::Result {
+        self.fmt(f)
+    }
+}
+
+/// A generic [`Display`] implementation for a [`DynamicDisplay`] implementor.
+pub struct DynamicDisplayer<'a, 'w>(&'a dyn DynamicDisplay, &'a WidgetContext<'w>);
+
+impl Display for DynamicDisplayer<'_, '_> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(self.1, f)
+    }
+}

src/widgets/list.rs

@@ -3,9 +3,21 @@
 use std::fmt::Debug;
 use std::sync::Arc;
 
+use nominals::{
+    ArmenianLower, ArmenianUpper, Bengali, Cambodian, CjkDecimal, CjkEarthlyBranch,
+    CjkHeavenlyStem, Decimal, Devanagari, DigitCollection, EasternArabic, Ethiopic, Georgian,
+    GreekLower, GreekUpper, Gujarati, Gurmukhi, HangeulFormal, HangeulInformal, HangeulJamo,
+    HangeulSyllable, HanjaFormal, Hebrew, HexLower, HexUpper, Hiragana, HiraganaIroha,
+    JapaneseFormal, JapaneseInformal, Kannada, Katakana, KatakanaIroha, Lao, LetterLower,
+    LetterUpper, Malayalam, Mongolian, Myanmar, NominalSystem, Oriya, Persian, RomanLower,
+    RomanUpper, Tamil, Telugu, Thai, Tibetan,
+};
+
 use super::grid::GridWidgets;
 use super::input::CowString;
-use super::Grid;
+use super::label::DynamicDisplay;
+use super::{Grid, Label};
+use crate::styles::{Component, RequireInvalidation};
 use crate::value::{IntoValue, MapEach, Source, Value};
 use crate::widget::{MakeWidget, WidgetInstance, WidgetList};
 
@@ -16,25 +28,198 @@ pub struct List {
 }
 
 impl List {
-    /// Returns a new list with the default [`ListStyle`]/
+    /// Returns a new list with the default [`ListStyle`].
+    #[must_use]
     pub fn new(children: impl IntoValue<WidgetList>) -> Self {
         Self {
             children: children.into_value(),
             style: Value::Constant(ListStyle::default()),
         }
     }
+
+    /// Sets the style of list identifiers to `style`.
+    #[must_use]
+    pub fn style(mut self, style: impl IntoValue<ListStyle>) -> Self {
+        self.style = style.into_value();
+        self
+    }
 }
 
 /// The style of a [`List`] widget's item indicators.
 #[derive(Default, Debug, Clone)]
 pub enum ListStyle {
+    /// This list should have no indicators.
+    None,
+
     /// A solid circle indicator, using the unicode bullet indicator.
     #[default]
     Disc,
+    /// A hollow circle.
+    Circle,
+    /// A filled square.
+    Square,
+
+    /// Decimal digits (0-9).
+    Decimal,
+    /// Eastern Arabic digits.
+    EasternArabic,
+    /// Persian digits.
+    Persian,
+
+    /// Lowercase Armenian numbering.
+    ArmenianLower,
+    /// Uppercase Armenian numbering.
+    ArmenianUpper,
+    /// Bengali numeric digits.
+    Bengali,
+    /// Cambodian numeric digits.
+    Cambodian,
+    /// CJK Han decimal digits.
+    CjkDecimal,
+    /// CJK Earthly Branch symbols.
+    ///
+    /// This digit collection back to [`CjkDecimal`] after the set is enumerated.
+    CjkEarthlyBranch,
+    /// CJK Heavenly Stems symbols.
+    ///
+    /// This digit collection falls back to [`CjkDecimal`] after the set is
+    /// enumerated.
+    CjkHeavenlyStem,
+    /// Devanagari numeric digits.
+    Devanagari,
+    /// Ethiopic numerical system.
+    Ethiopic,
+    /// Traditional Georgian numbering.
+    Georgian,
+    /// Gujarati numeric digits.
+    Gujarati,
+    /// Gurmukhi numeric digits.
+    Gurmukhi,
+    /// Korean Hangeul numbering.
+    HangeulFormal,
+    /// Informal Korean Hangeul numbering.
+    HangeulInformal,
+    /// Formal Korean Hanja numbering.
+    HanjaFormal,
+    /// Formal Japanese Kanji numbering.
+    JapaneseFormal,
+    /// Informal Japanese Kanji numbering.
+    JapaneseInformal,
+    /// Kannada numeric digits.
+    Kannada,
+    /// Lao numeric digits.
+    Lao,
+    /// Malayalam numeric digits.
+    Malayalam,
+    /// Mongolian numeric digits.
+    Mongolian,
+    /// Myanmar numeric digits.
+    Myanmar,
+    /// Oriya numeric digits.
+    Oriya,
+    /// Tamil numeric digits.
+    Tamil,
+    /// Telugu numeric digits.
+    Telugu,
+    /// Thai numeric digits.
+    Thai,
+    /// Tibetan numeric digits.
+    Tibetan,
+
+    /// ASCII lowercase alphabet (a-z).
+    LetterLower,
+    /// ASCII uppercase alphabet (A-Z).
+    LetterUpper,
+    /// Hexadecimal lowercase digits (0-9a-f)
+    HexLower,
+    /// Hexadecimal uppercase digits (0-9A-F)
+    HexUpper,
+    /// Greek lowercase alphabet.
+    GreekUpper,
+    /// Greek uppercase alphabet.
+    GreekLower,
+    /// Japanese Hiragana Aiueo alphabet.
+    Hiragana,
+    /// Japanese Hiragana Iroha alphabet.
+    HiraganaIroha,
+    /// Japanese Katakana Aiueo alphabet.
+    Katakana,
+    /// Japanese Katakana Iroha alphabet.
+    KatakanaIroha,
+    /// Korean Hangeul Jamo alphabet.
+    HangeulJamo,
+    /// Korean Hangeul Syllable alphabet.
+    HangeulSyllable,
+
+    /// Lowercase Roman numerals (i, ii, iii, iv, ...).
+    RomanLower,
+    /// Uppercase Roman numerals (I, II, III, IV, ...).
+    RomanUpper,
+    /// Hebrew numerals.
+    Hebrew,
+
     /// A custom list indicator style.
     Custom(Arc<dyn ListIndicator>),
 }
 
+impl ListStyle {
+    /// Returns an iterator containing all built-in list styles.
+    #[must_use]
+    pub const fn provided() -> impl IntoIterator<Item = ListStyle> {
+        [
+            ListStyle::None,
+            ListStyle::Disc,
+            ListStyle::Circle,
+            ListStyle::Square,
+            ListStyle::Decimal,
+            ListStyle::ArmenianLower,
+            ListStyle::ArmenianUpper,
+            ListStyle::Bengali,
+            ListStyle::Cambodian,
+            ListStyle::CjkDecimal,
+            ListStyle::CjkEarthlyBranch,
+            ListStyle::CjkHeavenlyStem,
+            ListStyle::Devanagari,
+            ListStyle::EasternArabic,
+            ListStyle::Ethiopic,
+            ListStyle::Georgian,
+            ListStyle::GreekLower,
+            ListStyle::GreekUpper,
+            ListStyle::Gujarati,
+            ListStyle::Gurmukhi,
+            ListStyle::HangeulFormal,
+            ListStyle::HangeulInformal,
+            ListStyle::HangeulJamo,
+            ListStyle::HangeulSyllable,
+            ListStyle::HanjaFormal,
+            ListStyle::Hebrew,
+            ListStyle::HexLower,
+            ListStyle::HexUpper,
+            ListStyle::Hiragana,
+            ListStyle::HiraganaIroha,
+            ListStyle::JapaneseFormal,
+            ListStyle::JapaneseInformal,
+            ListStyle::Kannada,
+            ListStyle::Katakana,
+            ListStyle::KatakanaIroha,
+            ListStyle::Lao,
+            ListStyle::LetterLower,
+            ListStyle::LetterUpper,
+            ListStyle::Malayalam,
+            ListStyle::Mongolian,
+            ListStyle::Myanmar,
+            ListStyle::Oriya,
+            ListStyle::Persian,
+            ListStyle::RomanLower,
+            ListStyle::RomanUpper,
+            ListStyle::Tamil,
+            ListStyle::Telugu,
+            ListStyle::Thai,
+            ListStyle::Tibetan,
+        ]
+    }
+}
+
 impl PartialEq for ListStyle {
     fn eq(&self, other: &Self) -> bool {
         match (self, other) {
@@ -48,14 +233,153 @@ impl PartialEq for ListStyle {
 /// given list index.
 pub trait ListIndicator: Debug + Sync + Send + 'static {
     /// Returns the indicator to use at `index`.
-    fn list_indicator(&self, index: usize) -> Option<CowString>;
+    fn list_indicator(&self, index: usize) -> Option<Indicator>;
 }
 
 impl ListIndicator for ListStyle {
-    fn list_indicator(&self, index: usize) -> Option<CowString> {
+    #[allow(clippy::too_many_lines)] // can't avoid the match
+    fn list_indicator(&self, index: usize) -> Option<Indicator> {
         match self {
-            ListStyle::Disc => Some(CowString::new("\u{2022}")),
+            ListStyle::None => None,
+            ListStyle::Decimal => Some(Indicator::delimited(String::from(
+                Decimal.one_based().format_nominal(index),
+            ))),
+            ListStyle::Disc => Some(Indicator::bare(CowString::new("\u{2022}"))),
+            ListStyle::Circle => Some(Indicator::bare(CowString::new("\u{25E6}"))),
+            ListStyle::Square => Some(Indicator::bare(CowString::new("\u{25AA}"))),
             ListStyle::Custom(style) => style.list_indicator(index),
+            ListStyle::EasternArabic => Some(Indicator::delimited(String::from(
+                EasternArabic.one_based().format_nominal(index),
+            ))),
+            ListStyle::Persian => Some(Indicator::delimited(String::from(
+                Persian.one_based().format_nominal(index),
+            ))),
+            ListStyle::LetterLower => Some(Indicator::delimited(String::from(
+                LetterLower.one_based().format_nominal(index),
+            ))),
+            ListStyle::LetterUpper => Some(Indicator::delimited(String::from(
+                LetterUpper.one_based().format_nominal(index),
+            ))),
+            ListStyle::HexLower => Some(Indicator::delimited(String::from(
+                HexLower.one_based().format_nominal(index),
+            ))),
+            ListStyle::HexUpper => Some(Indicator::delimited(String::from(
+                HexUpper.one_based().format_nominal(index),
+            ))),
+            ListStyle::GreekUpper => Some(Indicator::delimited(String::from(
+                GreekUpper.one_based().format_nominal(index),
+            ))),
+            ListStyle::GreekLower => Some(Indicator::delimited(String::from(
+                GreekLower.one_based().format_nominal(index),
+            ))),
+            ListStyle::Hiragana => Some(Indicator::delimited(String::from(
+                Hiragana.one_based().format_nominal(index),
+            ))),
+            ListStyle::HiraganaIroha => Some(Indicator::delimited(String::from(
+                HiraganaIroha.one_based().format_nominal(index),
+            ))),
+            ListStyle::Katakana => Some(Indicator::delimited(String::from(
+                Katakana.one_based().format_nominal(index),
+            ))),
+            ListStyle::KatakanaIroha => Some(Indicator::delimited(String::from(
+                KatakanaIroha.one_based().format_nominal(index),
+            ))),
+            ListStyle::HangeulJamo => Some(Indicator::delimited(String::from(
+                HangeulJamo.one_based().format_nominal(index),
+            ))),
+            ListStyle::HangeulSyllable => Some(Indicator::delimited(String::from(
+                HangeulSyllable.one_based().format_nominal(index),
+            ))),
+            ListStyle::RomanLower => Some(Indicator::delimited(String::from(
+                RomanLower.format_nominal(index),
+            ))),
+            ListStyle::RomanUpper => Some(Indicator::delimited(String::from(
+                RomanUpper.format_nominal(index),
+            ))),
+            ListStyle::Hebrew => Some(Indicator::delimited(String::from(
+                Hebrew.format_nominal(index),
+            ))),
+            ListStyle::ArmenianLower => Some(Indicator::delimited(String::from(
+                ArmenianLower.format_nominal(index),
+            ))),
+            ListStyle::ArmenianUpper => Some(Indicator::delimited(String::from(
+                ArmenianUpper.format_nominal(index),
+            ))),
+            ListStyle::Bengali => Some(Indicator::delimited(String::from(
+                Bengali.one_based().format_nominal(index),
+            ))),
+            ListStyle::Cambodian => Some(Indicator::delimited(String::from(
+                Cambodian.one_based().format_nominal(index),
+            ))),
+            ListStyle::CjkDecimal => Some(Indicator::delimited(String::from(
+                CjkDecimal.one_based().format_nominal(index),
+            ))),
+            ListStyle::CjkEarthlyBranch => Some(Indicator::delimited(String::from(
+                CjkEarthlyBranch.one_based().format_nominal(index),
+            ))),
+            ListStyle::CjkHeavenlyStem => Some(Indicator::delimited(String::from(
+                CjkHeavenlyStem.one_based().format_nominal(index),
+            ))),
+            ListStyle::Devanagari => Some(Indicator::delimited(String::from(
+                Devanagari.one_based().format_nominal(index),
+            ))),
+            ListStyle::Ethiopic => Some(Indicator::delimited(String::from(
+                Ethiopic.format_nominal(index),
+            ))),
+            ListStyle::Georgian => Some(Indicator::delimited(String::from(
+                Georgian.format_nominal(index),
+            ))),
+            ListStyle::Gujarati => Some(Indicator::delimited(String::from(
+                Gujarati.one_based().format_nominal(index),
+            ))),
+            ListStyle::Gurmukhi => Some(Indicator::delimited(String::from(
+                Gurmukhi.one_based().format_nominal(index),
+            ))),
+            ListStyle::HangeulFormal => Some(Indicator::delimited(String::from(
+                HangeulFormal.format_nominal(index),
+            ))),
+            ListStyle::HangeulInformal => Some(Indicator::delimited(String::from(
+                HangeulInformal.format_nominal(index),
+            ))),
+            ListStyle::HanjaFormal => Some(Indicator::delimited(String::from(
+                HanjaFormal.format_nominal(index),
+            ))),
+            ListStyle::JapaneseFormal => Some(Indicator::delimited(String::from(
+                JapaneseFormal.format_nominal(index),
+            ))),
+            ListStyle::JapaneseInformal => Some(Indicator::delimited(String::from(
+                JapaneseInformal.format_nominal(index),
+            ))),
+            ListStyle::Kannada => Some(Indicator::delimited(String::from(
+                Kannada.one_based().format_nominal(index),
+            ))),
+            ListStyle::Lao => Some(Indicator::delimited(String::from(
+                Lao.one_based().format_nominal(index),
+            ))),
+            ListStyle::Malayalam => Some(Indicator::delimited(String::from(
+                Malayalam.one_based().format_nominal(index),
+            ))),
+            ListStyle::Mongolian => Some(Indicator::delimited(String::from(
+                Mongolian.one_based().format_nominal(index),
+            ))),
+            ListStyle::Myanmar => Some(Indicator::delimited(String::from(
+                Myanmar.one_based().format_nominal(index),
+            ))),
+            ListStyle::Oriya => Some(Indicator::delimited(String::from(
+                Oriya.one_based().format_nominal(index),
+            ))),
+            ListStyle::Tamil => Some(Indicator::delimited(String::from(
+                Tamil.one_based().format_nominal(index),
+            ))),
+            ListStyle::Telugu => Some(Indicator::delimited(String::from(
+                Telugu.one_based().format_nominal(index),
+            ))),
+            ListStyle::Thai => Some(Indicator::delimited(String::from(
+                Thai.one_based().format_nominal(index),
+            ))),
+            ListStyle::Tibetan => Some(Indicator::delimited(String::from(
+                Tibetan.one_based().format_nominal(index),
+            ))),
         }
     }
 }
@@ -86,9 +410,99 @@ fn build_grid_widgets(style: &ListStyle, children: &WidgetList) -> GridWidgets<2
         .enumerate()
         .map(|(index, child)| {
             (
-                style.list_indicator(index).unwrap_or_default(),
+                Label::new(
+                    style
+                        .list_indicator(index.wrapping_add(1))
+                        .unwrap_or_default(),
+                )
+                .align_right(),
                 child.clone().align_left().make_widget(),
             )
         })
         .collect()
 }
+
+/// An indicator used in a [`List`] widget.
+#[derive(Default, Debug, Clone, Eq, PartialEq)]
+pub struct Indicator {
+    display: CowString,
+    delimited: bool,
+}
+
+impl Indicator {
+    /// Returns an indicator that should show a [`Delimiter`] between itself and
+    /// the list item.
+    pub fn delimited(display: impl Into<CowString>) -> Self {
+        Self {
+            display: display.into(),
+            delimited: true,
+        }
+    }
+
+    /// Returns an indicator that skips rendering a [`Delimiter`].
+    pub fn bare(display: impl Into<CowString>) -> Self {
+        Self {
+            display: display.into(),
+            delimited: false,
+        }
+    }
+}
+
+impl DynamicDisplay for Indicator {
+    fn fmt(
+        &self,
+        context: &crate::context::WidgetContext<'_>,
+        f: &mut std::fmt::Formatter<'_>,
+    ) -> std::fmt::Result {
+        let prefix = context.get(&Prefix);
+        if self.delimited {
+            let delimiter = context.get(&TrailingDelimiter);
+            write!(f, "{}{}{}", prefix.0, self.display, delimiter.0)
+        } else {
+            write!(f, "{}{}", prefix.0, self.display)
+        }
+    }
+}
+
+/// A [`CowString`] type used in [`List`] widget style components.
+#[derive(Default)]
+pub struct ListDelimiter(CowString);
+
+impl From<&'_ str> for ListDelimiter {
+    fn from(value: &'_ str) -> Self {
+        Self(value.into())
+    }
+}
+
+impl From<ListDelimiter> for Component {
+    fn from(value: ListDelimiter) -> Self {
+        Component::String(value.0)
+    }
+}
+
+impl TryFrom<Component> for ListDelimiter {
+    type Error = Component;
+
+    fn try_from(value: Component) -> Result<Self, Self::Error> {
+        CowString::try_from(value).map(Self)
+    }
+}
+
+impl RequireInvalidation for ListDelimiter {
+    fn requires_invalidation(&self) -> bool {
+        true
+    }
+}
+
+define_components! {
+    List {
+        /// The delimiter to place between nested lists when using merged list
+        /// indicators.
+        Delimiter(ListDelimiter, "delimiter", ".".into())
+        /// The delimiter to place after the list indictor, when the list is
+        /// ordered.
+        TrailingDelimiter(ListDelimiter, "trailing_delimiter", @Delimiter)
+        /// The prefix to display before the list indicator.
+        Prefix(ListDelimiter, "prefix")
+    }
+}

src/widgets/radio.rs

@@ -52,7 +52,7 @@ impl<T> Radio<T> {
 
 impl<T> MakeWidgetWithTag for Radio<T>
 where
-    T: Clone + Debug + Eq + Send + 'static,
+    T: Clone + Debug + PartialEq + Send + 'static,
 {
     fn make_with_tag(self, id: crate::widget::WidgetTag) -> WidgetInstance {
         RadioOrnament {
@@ -78,7 +78,7 @@ struct RadioOrnament<T> {
 
 impl<T> Widget for RadioOrnament<T>
 where
-    T: Debug + Eq + Send + 'static,
+    T: Debug + PartialEq + Send + 'static,
 {
     fn redraw(&mut self, context: &mut GraphicsContext<'_, '_, '_, '_>) {
         let radio_size = context

src/widgets/select.rs

@@ -47,7 +47,7 @@ impl<T> Select<T> {
 
 impl<T> MakeWidgetWithTag for Select<T>
 where
-    T: Clone + Debug + Eq + Send + Sync + 'static,
+    T: Clone + Debug + PartialEq + Send + Sync + 'static,
 {
     fn make_with_tag(self, id: crate::widget::WidgetTag) -> WidgetInstance {
         let selected = self.state.map_each({