Merge pull request #2363 from iced-rs/specialize-text-helper

Specialize `widget::text` helper

core/src/widget/text.rs

@@ -21,7 +21,7 @@ where
     Theme: Catalog,
     Renderer: text::Renderer,
 {
-    content: Cow<'a, str>,
+    fragment: Fragment<'a>,
     size: Option<Pixels>,
     line_height: LineHeight,
     width: Length,
@@ -39,9 +39,9 @@ where
     Renderer: text::Renderer,
 {
     /// Create a new fragment of [`Text`] with the given contents.
-    pub fn new(content: impl Into<Cow<'a, str>>) -> Self {
+    pub fn new(fragment: impl IntoFragment<'a>) -> Self {
         Text {
-            content: content.into(),
+            fragment: fragment.into_fragment(),
             size: None,
             line_height: LineHeight::default(),
             font: None,
@@ -184,7 +184,7 @@ where
             limits,
             self.width,
             self.height,
-            &self.content,
+            &self.fragment,
             self.line_height,
             self.size,
             self.font,
@@ -366,3 +366,69 @@ impl Catalog for Theme {
         class(self)
     }
 }
+
+/// A fragment of [`Text`].
+///
+/// This is just an alias to a string that may be either
+/// borrowed or owned.
+pub type Fragment<'a> = Cow<'a, str>;
+
+/// A trait for converting a value to some text [`Fragment`].
+pub trait IntoFragment<'a> {
+    /// Converts the value to some text [`Fragment`].
+    fn into_fragment(self) -> Fragment<'a>;
+}
+
+impl<'a> IntoFragment<'a> for &'a str {
+    fn into_fragment(self) -> Fragment<'a> {
+        Fragment::Borrowed(self)
+    }
+}
+
+impl<'a> IntoFragment<'a> for &'a String {
+    fn into_fragment(self) -> Fragment<'a> {
+        Fragment::Borrowed(self.as_str())
+    }
+}
+
+impl<'a> IntoFragment<'a> for String {
+    fn into_fragment(self) -> Fragment<'a> {
+        Fragment::Owned(self)
+    }
+}
+
+macro_rules! into_fragment {
+    ($type:ty) => {
+        impl<'a> IntoFragment<'a> for $type {
+            fn into_fragment(self) -> Fragment<'a> {
+                Fragment::Owned(self.to_string())
+            }
+        }
+
+        impl<'a> IntoFragment<'a> for &$type {
+            fn into_fragment(self) -> Fragment<'a> {
+                Fragment::Owned(self.to_string())
+            }
+        }
+    };
+}
+
+into_fragment!(char);
+into_fragment!(bool);
+
+into_fragment!(u8);
+into_fragment!(u16);
+into_fragment!(u32);
+into_fragment!(u64);
+into_fragment!(u128);
+into_fragment!(usize);
+
+into_fragment!(i8);
+into_fragment!(i16);
+into_fragment!(i32);
+into_fragment!(i64);
+into_fragment!(i128);
+into_fragment!(isize);
+
+into_fragment!(f32);
+into_fragment!(f64);

examples/lazy/src/main.rs

@@ -173,7 +173,7 @@ impl App {
                     .style(button::danger);
 
                 row![
-                    text(&item.name).color(item.color),
+                    text(item.name.clone()).color(item.color),
                     horizontal_space(),
                     pick_list(Color::ALL, Some(item.color), move |color| {
                         Message::ItemColorChanged(item.clone(), color)

examples/tour/src/main.rs

@@ -357,7 +357,7 @@ impl<'a> Step {
         .into()
     }
 
-    fn container(title: &str) -> Column<'a, StepMessage> {
+    fn container(title: &str) -> Column<'_, StepMessage> {
         column![text(title).size(50)].spacing(20)
     }
 
@@ -589,7 +589,7 @@ impl<'a> Step {
         value: &str,
         is_secure: bool,
         is_showing_icon: bool,
-    ) -> Column<'a, StepMessage> {
+    ) -> Column<'_, StepMessage> {
         let mut text_input = text_input("Type something to continue...", value)
             .on_input(StepMessage::InputChanged)
             .padding(10)
@@ -674,7 +674,7 @@ fn ferris<'a>(
     .center_x()
 }
 
-fn padded_button<'a, Message: Clone>(label: &str) -> Button<'a, Message> {
+fn padded_button<Message: Clone>(label: &str) -> Button<'_, Message> {
     button(text(label)).padding([12, 24])
 }
 

examples/websocket/src/echo.rs

@@ -2,6 +2,7 @@ pub mod server;
 
 use iced::futures;
 use iced::subscription::{self, Subscription};
+use iced::widget::text;
 
 use futures::channel::mpsc;
 use futures::sink::SinkExt;
@@ -136,16 +137,24 @@ impl Message {
     pub fn disconnected() -> Self {
         Message::Disconnected
     }
+
+    pub fn as_str(&self) -> &str {
+        match self {
+            Message::Connected => "Connected successfully!",
+            Message::Disconnected => "Connection lost... Retrying...",
+            Message::User(message) => message.as_str(),
+        }
+    }
 }
 
 impl fmt::Display for Message {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self {
-            Message::Connected => write!(f, "Connected successfully!"),
-            Message::Disconnected => {
-                write!(f, "Connection lost... Retrying...")
-            }
-            Message::User(message) => write!(f, "{message}"),
-        }
+        f.write_str(self.as_str())
+    }
+}
+
+impl<'a> text::IntoFragment<'a> for &'a Message {
+    fn into_fragment(self) -> text::Fragment<'a> {
+        text::Fragment::Borrowed(self.as_str())
     }
 }

examples/websocket/src/main.rs

@@ -96,10 +96,8 @@ impl WebSocket {
             .into()
         } else {
             scrollable(
-                column(
-                    self.messages.iter().cloned().map(text).map(Element::from),
-                )
-                .spacing(10),
+                column(self.messages.iter().map(text).map(Element::from))
+                    .spacing(10),
             )
             .id(MESSAGE_LOG.clone())
             .height(Length::Fill)

widget/src/helpers.rs

@@ -145,13 +145,26 @@ where
 ///
 /// [`Text`]: core::widget::Text
 pub fn text<'a, Theme, Renderer>(
-    text: impl ToString,
+    text: impl text::IntoFragment<'a>,
 ) -> Text<'a, Theme, Renderer>
 where
     Theme: text::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
-    Text::new(text.to_string())
+    Text::new(text)
+}
+
+/// Creates a new [`Text`] widget that displays the provided value.
+///
+/// [`Text`]: core::widget::Text
+pub fn value<'a, Theme, Renderer>(
+    value: impl ToString,
+) -> Text<'a, Theme, Renderer>
+where
+    Theme: text::Catalog + 'a,
+    Renderer: core::text::Renderer,
+{
+    Text::new(value.to_string())
 }
 
 /// Creates a new [`Checkbox`].