Flesh out the markdown example a bit more

widget/src/helpers.rs

@@ -24,7 +24,7 @@ use crate::tooltip::{self, Tooltip};
 use crate::vertical_slider::{self, VerticalSlider};
 use crate::{Column, MouseArea, Row, Space, Stack, Themer};
 
-use std::borrow::Borrow;
+use std::borrow::{Borrow, Cow};
 use std::ops::RangeInclusive;
 
 /// Creates a [`Column`] with the given children.
@@ -684,7 +684,7 @@ where
 ///
 /// [`Rich`]: text::Rich
 pub fn rich_text<'a, Theme, Renderer>(
-    spans: impl IntoIterator<Item = text::Span<'a, Renderer::Font>>,
+    spans: impl Into<Cow<'a, [text::Span<'a, Renderer::Font>]>>,
 ) -> text::Rich<'a, Theme, Renderer>
 where
     Theme: text::Catalog + 'a,

widget/src/text.rs

@@ -1,7 +1,7 @@
 //! Draw and interact with text.
 mod rich;
 
-pub use crate::core::text::{Fragment, IntoFragment, Span};
+pub use crate::core::text::{Fragment, Highlighter, IntoFragment, Span};
 pub use crate::core::widget::text::*;
 pub use rich::Rich;
 

widget/src/text/rich.rs

@@ -11,6 +11,8 @@ use crate::core::{
     self, Color, Element, Length, Pixels, Rectangle, Size, Widget,
 };
 
+use std::borrow::Cow;
+
 /// A bunch of [`Rich`] text.
 #[derive(Debug)]
 pub struct Rich<'a, Theme = crate::Theme, Renderer = crate::Renderer>
@@ -18,7 +20,7 @@ where
     Theme: Catalog,
     Renderer: core::text::Renderer,
 {
-    spans: Vec<Span<'a, Renderer::Font>>,
+    spans: Cow<'a, [Span<'a, Renderer::Font>]>,
     size: Option<Pixels>,
     line_height: LineHeight,
     width: Length,
@@ -37,7 +39,7 @@ where
     /// Creates a new empty [`Rich`] text.
     pub fn new() -> Self {
         Self {
-            spans: Vec::new(),
+            spans: Cow::default(),
             size: None,
             line_height: LineHeight::default(),
             width: Length::Shrink,
@@ -51,10 +53,10 @@ where
 
     /// Creates a new [`Rich`] text with the given text spans.
     pub fn with_spans(
-        spans: impl IntoIterator<Item = Span<'a, Renderer::Font>>,
+        spans: impl Into<Cow<'a, [Span<'a, Renderer::Font>]>>,
     ) -> Self {
         Self {
-            spans: spans.into_iter().collect(),
+            spans: spans.into(),
             ..Self::new()
         }
     }
@@ -151,7 +153,7 @@ where
 
     /// Adds a new text [`Span`] to the [`Rich`] text.
     pub fn push(mut self, span: impl Into<Span<'a, Renderer::Font>>) -> Self {
-        self.spans.push(span.into());
+        self.spans.to_mut().push(span.into());
         self
     }
 }
@@ -207,7 +209,7 @@ where
             limits,
             self.width,
             self.height,
-            self.spans.as_slice(),
+            self.spans.as_ref(),
             self.line_height,
             self.size,
             self.font,
@@ -303,6 +305,22 @@ where
     })
 }
 
+impl<'a, Theme, Renderer> FromIterator<Span<'a, Renderer::Font>>
+    for Rich<'a, Theme, Renderer>
+where
+    Theme: Catalog,
+    Renderer: core::text::Renderer,
+{
+    fn from_iter<T: IntoIterator<Item = Span<'a, Renderer::Font>>>(
+        spans: T,
+    ) -> Self {
+        Self {
+            spans: spans.into_iter().collect(),
+            ..Self::new()
+        }
+    }
+}
+
 impl<'a, Message, Theme, Renderer> From<Rich<'a, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where

widget/src/text_editor.rs

@@ -9,6 +9,7 @@ use crate::core::renderer;
 use crate::core::text::editor::{Cursor, Editor as _};
 use crate::core::text::highlighter::{self, Highlighter};
 use crate::core::text::{self, LineHeight};
+use crate::core::widget::operation;
 use crate::core::widget::{self, Widget};
 use crate::core::{
     Background, Border, Color, Element, Length, Padding, Pixels, Rectangle,
@@ -338,6 +339,22 @@ impl<Highlighter: text::Highlighter> State<Highlighter> {
     }
 }
 
+impl<Highlighter: text::Highlighter> operation::Focusable
+    for State<Highlighter>
+{
+    fn is_focused(&self) -> bool {
+        self.is_focused
+    }
+
+    fn focus(&mut self) {
+        self.is_focused = true;
+    }
+
+    fn unfocus(&mut self) {
+        self.is_focused = false;
+    }
+}
+
 impl<'a, Highlighter, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for TextEditor<'a, Highlighter, Message, Theme, Renderer>
 where
@@ -640,6 +657,18 @@ where
             mouse::Interaction::default()
         }
     }
+
+    fn operate(
+        &self,
+        tree: &mut widget::Tree,
+        _layout: Layout<'_>,
+        _renderer: &Renderer,
+        operation: &mut dyn widget::Operation<()>,
+    ) {
+        let state = tree.state.downcast_mut::<State<Highlighter>>();
+
+        operation.focusable(state, None);
+    }
 }
 
 impl<'a, Highlighter, Message, Theme, Renderer>