Add .id method and text_editor::focus task

examples/editor/src/main.rs

@@ -1,7 +1,7 @@
 use iced::highlighter;
 use iced::keyboard;
 use iced::widget::{
-    self, button, column, container, horizontal_space, pick_list, row, text,
+    button, column, container, horizontal_space, pick_list, row, text,
     text_editor, toggler, tooltip,
 };
 use iced::{Center, Element, Fill, Font, Task, Theme};
@@ -20,6 +20,7 @@ pub fn main() -> iced::Result {
 }
 
 struct Editor {
+    editor_id: text_editor::Id,
     file: Option<PathBuf>,
     content: text_editor::Content,
     theme: highlighter::Theme,
@@ -42,8 +43,10 @@ enum Message {
 
 impl Editor {
     fn new() -> (Self, Task<Message>) {
+        let id = text_editor::Id::unique();
         (
             Self {
+                editor_id: id.clone(),
                 file: None,
                 content: text_editor::Content::new(),
                 theme: highlighter::Theme::SolarizedDark,
@@ -59,7 +62,7 @@ impl Editor {
                     )),
                     Message::FileOpened,
                 ),
-                widget::focus_next(),
+                text_editor::focus(id),
             ]),
         )
     }
@@ -188,6 +191,7 @@ impl Editor {
         column![
             controls,
             text_editor(&self.content)
+                .id(self.editor_id.clone())
                 .height(Fill)
                 .on_action(Message::ActionPerformed)
                 .wrapping(if self.word_wrap {

widget/src/text_editor.rs

@@ -51,6 +51,9 @@ use crate::core::{
     Rectangle, Shell, Size, SmolStr, Theme, Vector,
 };
 
+use crate::runtime::task::{self, Task};
+use crate::runtime::Action as RuntimeAction;
+
 use std::cell::RefCell;
 use std::fmt;
 use std::ops::DerefMut;
@@ -103,6 +106,7 @@ pub struct TextEditor<
     Theme: Catalog,
     Renderer: text::Renderer,
 {
+    id: Option<Id>,
     content: &'a Content<Renderer>,
     placeholder: Option<text::Fragment<'a>>,
     font: Option<Renderer::Font>,
@@ -131,6 +135,7 @@ where
     /// Creates new [`TextEditor`] with the given [`Content`].
     pub fn new(content: &'a Content<Renderer>) -> Self {
         Self {
+            id: None,
             content,
             placeholder: None,
             font: None,
@@ -149,6 +154,12 @@ where
             },
         }
     }
+
+    /// Sets the [`Id`] of the [`TextEditor`].
+    pub fn id(mut self, id: impl Into<Id>) -> Self {
+        self.id = Some(id.into());
+        self
+    }
 }
 
 impl<'a, Highlighter, Message, Theme, Renderer>
@@ -256,6 +267,7 @@ where
         ) -> highlighter::Format<Renderer::Font>,
     ) -> TextEditor<'a, H, Message, Theme, Renderer> {
         TextEditor {
+            id: self.id,
             content: self.content,
             placeholder: self.placeholder,
             font: self.font,
@@ -958,7 +970,7 @@ where
     ) {
         let state = tree.state.downcast_mut::<State<Highlighter>>();
 
-        operation.focusable(state, None);
+        operation.focusable(state, self.id.as_ref().map(|id| &id.0));
     }
 }
 
@@ -978,6 +990,49 @@ where
     }
 }
 
+/// The identifier of a [`TextEditor`].
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct Id(widget::Id);
+
+impl Id {
+    /// Creates a custom [`Id`].
+    pub fn new(id: impl Into<std::borrow::Cow<'static, str>>) -> Self {
+        Self(widget::Id::new(id))
+    }
+
+    /// Creates a unique [`Id`].
+    ///
+    /// This function produces a different [`Id`] every time it is called.
+    pub fn unique() -> Self {
+        Self(widget::Id::unique())
+    }
+}
+
+impl From<Id> for widget::Id {
+    fn from(id: Id) -> Self {
+        id.0
+    }
+}
+
+impl From<&'static str> for Id {
+    fn from(id: &'static str) -> Self {
+        Self::new(id)
+    }
+}
+
+impl From<String> for Id {
+    fn from(id: String) -> Self {
+        Self::new(id)
+    }
+}
+
+/// Produces a [`Task`] that focuses the [`TextEditor`] with the given [`Id`].
+pub fn focus<T>(id: impl Into<Id>) -> Task<T> {
+    task::effect(RuntimeAction::widget(operation::focusable::focus(
+        id.into().0,
+    )))
+}
+
 /// A binding to an action in the [`TextEditor`].
 #[derive(Debug, Clone, PartialEq)]
 pub enum Binding<Message> {