18 files changed, 481 insertions, 65 deletions

diff --git a/core/src/animation.rs b/core/src/animation.rs
index 258fd084..14cbb5c3 100644
--- a/core/src/animation.rs
+++ b/core/src/animation.rs
@@ -13,6 +13,7 @@ where
     T: Clone + Copy + PartialEq + Float,
 {
     raw: lilt::Animated<T, Instant>,
+    duration: Duration, // TODO: Expose duration getter in `lilt`
 }
 
 impl<T> Animation<T>
@@ -23,6 +24,7 @@ where
     pub fn new(state: T) -> Self {
         Self {
             raw: lilt::Animated::new(state),
+            duration: Duration::from_millis(100),
         }
     }
 
@@ -58,6 +60,7 @@ where
     /// Sets the duration of the [`Animation`] to the given value.
     pub fn duration(mut self, duration: Duration) -> Self {
         self.raw = self.raw.duration(duration.as_secs_f32() * 1_000.0);
+        self.duration = duration;
         self
     }
 
@@ -133,4 +136,13 @@ impl Animation<bool> {
     {
         self.raw.animate_bool(start, end, at)
     }
+
+    /// Returns the remaining [`Duration`] of the [`Animation`].
+    pub fn remaining(&self, at: Instant) -> Duration {
+        Duration::from_secs_f32(self.interpolate(
+            self.duration.as_secs_f32(),
+            0.0,
+            at,
+        ))
+    }
 }
diff --git a/core/src/element.rs b/core/src/element.rs
index 82ba753b..b7d51aeb 100644
--- a/core/src/element.rs
+++ b/core/src/element.rs
@@ -93,6 +93,7 @@ impl<'a, Message, Theme, Renderer> Element<'a, Message, Theme, Renderer> {
     ///
     /// ```no_run
     /// # mod iced {
+    /// #     pub use iced_core::Function;
     /// #     pub type Element<'a, Message> = iced_core::Element<'a, Message, iced_core::Theme, ()>;
     /// #
     /// #     pub mod widget {
@@ -119,7 +120,7 @@ impl<'a, Message, Theme, Renderer> Element<'a, Message, Theme, Renderer> {
     /// use counter::Counter;
     ///
     /// use iced::widget::row;
-    /// use iced::Element;
+    /// use iced::{Element, Function};
     ///
     /// struct ManyCounters {
     ///     counters: Vec<Counter>,
@@ -142,7 +143,7 @@ impl<'a, Message, Theme, Renderer> Element<'a, Message, Theme, Renderer> {
     ///                     // Here we turn our `Element<counter::Message>` into
     ///                     // an `Element<Message>` by combining the `index` and the
     ///                     // message of the `element`.
-    ///                     counter.map(move |message| Message::Counter(index, message))
+    ///                     counter.map(Message::Counter.with(index))
     ///                 }),
     ///         )
     ///         .into()
@@ -311,7 +312,7 @@ where
     fn update(
         &mut self,
         tree: &mut Tree,
-        event: Event,
+        event: &Event,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         renderer: &Renderer,
@@ -447,7 +448,7 @@ where
     fn update(
         &mut self,
         state: &mut Tree,
-        event: Event,
+        event: &Event,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         renderer: &Renderer,
diff --git a/core/src/event.rs b/core/src/event.rs
index b6cf321e..7f0ab914 100644
--- a/core/src/event.rs
+++ b/core/src/event.rs
@@ -1,4 +1,5 @@
 //! Handle events of a user interface.
+use crate::input_method;
 use crate::keyboard;
 use crate::mouse;
 use crate::touch;
@@ -23,6 +24,9 @@ pub enum Event {
 
     /// A touch event
     Touch(touch::Event),
+
+    /// An input method event
+    InputMethod(input_method::Event),
 }
 
 /// The status of an [`Event`] after being processed.
diff --git a/core/src/input_method.rs b/core/src/input_method.rs
new file mode 100644
index 00000000..cd8d459d
--- /dev/null
+++ b/core/src/input_method.rs
@@ -0,0 +1,221 @@
+//! Listen to input method events.
+use crate::{Pixels, Point};
+
+use std::ops::Range;
+
+/// The input method strategy of a widget.
+#[derive(Debug, Clone, PartialEq)]
+pub enum InputMethod<T = String> {
+    /// Input method is disabled.
+    Disabled,
+    /// Input method is enabled.
+    Enabled {
+        /// The position at which the input method dialog should be placed.
+        position: Point,
+        /// The [`Purpose`] of the input method.
+        purpose: Purpose,
+        /// The preedit to overlay on top of the input method dialog, if needed.
+        ///
+        /// Ideally, your widget will show pre-edits on-the-spot; but, since that can
+        /// be tricky, you can instead provide the current pre-edit here and the
+        /// runtime will display it as an overlay (i.e. "Over-the-spot IME").
+        preedit: Option<Preedit<T>>,
+    },
+}
+
+/// The pre-edit of an [`InputMethod`].
+#[derive(Debug, Clone, PartialEq, Default)]
+pub struct Preedit<T = String> {
+    /// The current content.
+    pub content: T,
+    /// The selected range of the content.
+    pub selection: Option<Range<usize>>,
+    /// The text size of the content.
+    pub text_size: Option<Pixels>,
+}
+
+impl<T> Preedit<T> {
+    /// Creates a new empty [`Preedit`].
+    pub fn new() -> Self
+    where
+        T: Default,
+    {
+        Self::default()
+    }
+
+    /// Turns a [`Preedit`] into its owned version.
+    pub fn to_owned(&self) -> Preedit
+    where
+        T: AsRef<str>,
+    {
+        Preedit {
+            content: self.content.as_ref().to_owned(),
+            selection: self.selection.clone(),
+            text_size: self.text_size,
+        }
+    }
+}
+
+impl Preedit {
+    /// Borrows the contents of a [`Preedit`].
+    pub fn as_ref(&self) -> Preedit<&str> {
+        Preedit {
+            content: &self.content,
+            selection: self.selection.clone(),
+            text_size: self.text_size,
+        }
+    }
+}
+
+/// The purpose of an [`InputMethod`].
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum Purpose {
+    /// No special hints for the IME (default).
+    #[default]
+    Normal,
+    /// The IME is used for secure input (e.g. passwords).
+    Secure,
+    /// The IME is used to input into a terminal.
+    ///
+    /// For example, that could alter OSK on Wayland to show extra buttons.
+    Terminal,
+}
+
+impl InputMethod {
+    /// Merges two [`InputMethod`] strategies, prioritizing the first one when both open:
+    /// ```
+    /// # use iced_core::input_method::{InputMethod, Purpose, Preedit};
+    /// # use iced_core::Point;
+    ///
+    /// let open = InputMethod::Enabled {
+    ///     position: Point::ORIGIN,
+    ///     purpose: Purpose::Normal,
+    ///     preedit: Some(Preedit { content: "1".to_owned(), selection: None, text_size: None }),
+    /// };
+    ///
+    /// let open_2 = InputMethod::Enabled {
+    ///     position: Point::ORIGIN,
+    ///     purpose: Purpose::Secure,
+    ///     preedit: Some(Preedit { content: "2".to_owned(), selection: None, text_size: None }),
+    /// };
+    ///
+    /// let mut ime = InputMethod::Disabled;
+    ///
+    /// ime.merge(&open);
+    /// assert_eq!(ime, open);
+    ///
+    /// ime.merge(&open_2);
+    /// assert_eq!(ime, open);
+    /// ```
+    pub fn merge<T: AsRef<str>>(&mut self, other: &InputMethod<T>) {
+        if let InputMethod::Enabled { .. } = self {
+            return;
+        }
+
+        *self = other.to_owned();
+    }
+
+    /// Returns true if the [`InputMethod`] is open.
+    pub fn is_enabled(&self) -> bool {
+        matches!(self, Self::Enabled { .. })
+    }
+}
+
+impl<T> InputMethod<T> {
+    /// Turns an [`InputMethod`] into its owned version.
+    pub fn to_owned(&self) -> InputMethod
+    where
+        T: AsRef<str>,
+    {
+        match self {
+            Self::Disabled => InputMethod::Disabled,
+            Self::Enabled {
+                position,
+                purpose,
+                preedit,
+            } => InputMethod::Enabled {
+                position: *position,
+                purpose: *purpose,
+                preedit: preedit.as_ref().map(Preedit::to_owned),
+            },
+        }
+    }
+}
+
+/// Describes [input method](https://en.wikipedia.org/wiki/Input_method) events.
+///
+/// This is also called a "composition event".
+///
+/// Most keypresses using a latin-like keyboard layout simply generate a
+/// [`keyboard::Event::KeyPressed`](crate::keyboard::Event::KeyPressed).
+/// However, one couldn't possibly have a key for every single
+/// unicode character that the user might want to type. The solution operating systems employ is
+/// to allow the user to type these using _a sequence of keypresses_ instead.
+///
+/// A prominent example of this is accents—many keyboard layouts allow you to first click the
+/// "accent key", and then the character you want to apply the accent to. In this case, some
+/// platforms will generate the following event sequence:
+///
+/// ```ignore
+/// // Press "`" key
+/// Ime::Preedit("`", Some((0, 0)))
+/// // Press "E" key
+/// Ime::Preedit("", None) // Synthetic event generated to clear preedit.
+/// Ime::Commit("é")
+/// ```
+///
+/// Additionally, certain input devices are configured to display a candidate box that allow the
+/// user to select the desired character interactively. (To properly position this box, you must use
+/// [`Shell::request_input_method`](crate::Shell::request_input_method).)
+///
+/// An example of a keyboard layout which uses candidate boxes is pinyin. On a latin keyboard the
+/// following event sequence could be obtained:
+///
+/// ```ignore
+/// // Press "A" key
+/// Ime::Preedit("a", Some((1, 1)))
+/// // Press "B" key
+/// Ime::Preedit("a b", Some((3, 3)))
+/// // Press left arrow key
+/// Ime::Preedit("a b", Some((1, 1)))
+/// // Press space key
+/// Ime::Preedit("啊b", Some((3, 3)))
+/// // Press space key
+/// Ime::Preedit("", None) // Synthetic event generated to clear preedit.
+/// Ime::Commit("啊不")
+/// ```
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub enum Event {
+    /// Notifies when the IME was opened.
+    ///
+    /// After getting this event you could receive [`Preedit`][Self::Preedit] and
+    /// [`Commit`][Self::Commit] events. You should also start performing IME related requests
+    /// like [`Shell::request_input_method`].
+    ///
+    /// [`Shell::request_input_method`]: crate::Shell::request_input_method
+    Opened,
+
+    /// Notifies when a new composing text should be set at the cursor position.
+    ///
+    /// The value represents a pair of the preedit string and the cursor begin position and end
+    /// position. When it's `None`, the cursor should be hidden. When `String` is an empty string
+    /// this indicates that preedit was cleared.
+    ///
+    /// The cursor range is byte-wise indexed.
+    Preedit(String, Option<Range<usize>>),
+
+    /// Notifies when text should be inserted into the editor widget.
+    ///
+    /// Right before this event, an empty [`Self::Preedit`] event will be issued.
+    Commit(String),
+
+    /// Notifies when the IME was disabled.
+    ///
+    /// After receiving this event you won't get any more [`Preedit`][Self::Preedit] or
+    /// [`Commit`][Self::Commit] events until the next [`Opened`][Self::Opened] event. You should
+    /// also stop issuing IME related requests like [`Shell::request_input_method`] and clear
+    /// pending preedit text.
+    ///
+    /// [`Shell::request_input_method`]: crate::Shell::request_input_method
+    Closed,
+}
diff --git a/core/src/length.rs b/core/src/length.rs
index 5f24169f..363833c4 100644
--- a/core/src/length.rs
+++ b/core/src/length.rs
@@ -77,8 +77,8 @@ impl From<f32> for Length {
     }
 }
 
-impl From<u16> for Length {
-    fn from(units: u16) -> Self {
-        Length::Fixed(f32::from(units))
+impl From<u32> for Length {
+    fn from(units: u32) -> Self {
+        Length::Fixed(units as f32)
     }
 }
diff --git a/core/src/lib.rs b/core/src/lib.rs
index 16b3aa0f..03cc0632 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -17,6 +17,7 @@ pub mod event;
 pub mod font;
 pub mod gradient;
 pub mod image;
+pub mod input_method;
 pub mod keyboard;
 pub mod layout;
 pub mod mouse;
@@ -61,6 +62,7 @@ pub use event::Event;
 pub use font::Font;
 pub use gradient::Gradient;
 pub use image::Image;
+pub use input_method::InputMethod;
 pub use layout::Layout;
 pub use length::Length;
 pub use overlay::Overlay;
@@ -82,3 +84,69 @@ pub use vector::Vector;
 pub use widget::Widget;
 
 pub use smol_str::SmolStr;
+
+/// A function that can _never_ be called.
+///
+/// This is useful to turn generic types into anything
+/// you want by coercing them into a type with no possible
+/// values.
+pub fn never<T>(never: std::convert::Infallible) -> T {
+    match never {}
+}
+
+/// A trait extension for binary functions (`Fn(A, B) -> O`).
+///
+/// It enables you to use a bunch of nifty functional programming paradigms
+/// that work well with iced.
+pub trait Function<A, B, O> {
+    /// Applies the given first argument to a binary function and returns
+    /// a new function that takes the other argument.
+    ///
+    /// This lets you partially "apply" a function—equivalent to currying,
+    /// but it only works with binary functions. If you want to apply an
+    /// arbitrary number of arguments, create a little struct for them.
+    ///
+    /// # When is this useful?
+    /// Sometimes you will want to identify the source or target
+    /// of some message in your user interface. This can be achieved through
+    /// normal means by defining a closure and moving the identifier
+    /// inside:
+    ///
+    /// ```rust
+    /// # let element: Option<()> = Some(());
+    /// # enum Message { ButtonPressed(u32, ()) }
+    /// let id = 123;
+    ///
+    /// # let _ = {
+    /// element.map(move |result| Message::ButtonPressed(id, result))
+    /// # };
+    /// ```
+    ///
+    /// That's quite a mouthful. [`with`](Self::with) lets you write:
+    ///
+    /// ```rust
+    /// # use iced_core::Function;
+    /// # let element: Option<()> = Some(());
+    /// # enum Message { ButtonPressed(u32, ()) }
+    /// let id = 123;
+    ///
+    /// # let _ = {
+    /// element.map(Message::ButtonPressed.with(id))
+    /// # };
+    /// ```
+    ///
+    /// Effectively creating the same closure that partially applies
+    /// the `id` to the message—but much more concise!
+    fn with(self, prefix: A) -> impl Fn(B) -> O;
+}
+
+impl<F, A, B, O> Function<A, B, O> for F
+where
+    F: Fn(A, B) -> O,
+    Self: Sized,
+    A: Copy,
+{
+    fn with(self, prefix: A) -> impl Fn(B) -> O {
+        move |result| self(prefix, result)
+    }
+}
diff --git a/core/src/mouse/cursor.rs b/core/src/mouse/cursor.rs
index 616cd315..9388a578 100644
--- a/core/src/mouse/cursor.rs
+++ b/core/src/mouse/cursor.rs
@@ -1,13 +1,14 @@
 use crate::{Point, Rectangle, Transformation, Vector};
 
-use std::ops::Mul;
-
 /// The mouse cursor state.
 #[derive(Debug, Clone, Copy, PartialEq, Default)]
 pub enum Cursor {
     /// The cursor has a defined position.
     Available(Point),
 
+    /// The cursor has a defined position, but it's levitating over a layer above.
+    Levitating(Point),
+
     /// The cursor is currently unavailable (i.e. out of bounds or busy).
     #[default]
     Unavailable,
@@ -18,7 +19,7 @@ impl Cursor {
     pub fn position(self) -> Option<Point> {
         match self {
             Cursor::Available(position) => Some(position),
-            Cursor::Unavailable => None,
+            Cursor::Levitating(_) | Cursor::Unavailable => None,
         }
     }
 
@@ -51,17 +52,41 @@ impl Cursor {
     pub fn is_over(self, bounds: Rectangle) -> bool {
         self.position_over(bounds).is_some()
     }
+
+    /// Returns true if the [`Cursor`] is levitating over a layer above.
+    pub fn is_levitating(self) -> bool {
+        matches!(self, Self::Levitating(_))
+    }
+
+    /// Makes the [`Cursor`] levitate over a layer above.
+    pub fn levitate(self) -> Self {
+        match self {
+            Self::Available(position) => Self::Levitating(position),
+            _ => self,
+        }
+    }
+
+    /// Brings the [`Cursor`] back to the current layer.
+    pub fn land(self) -> Self {
+        match self {
+            Cursor::Levitating(position) => Cursor::Available(position),
+            _ => self,
+        }
+    }
 }
 
-impl Mul<Transformation> for Cursor {
+impl std::ops::Mul<Transformation> for Cursor {
     type Output = Self;
 
     fn mul(self, transformation: Transformation) -> Self {
         match self {
-            Cursor::Unavailable => Cursor::Unavailable,
-            Cursor::Available(point) => {
-                Cursor::Available(point * transformation)
+            Self::Available(position) => {
+                Self::Available(position * transformation)
+            }
+            Self::Levitating(position) => {
+                Self::Levitating(position * transformation)
             }
+            Self::Unavailable => Self::Unavailable,
         }
     }
 }
diff --git a/core/src/overlay.rs b/core/src/overlay.rs
index 383663af..94239152 100644
--- a/core/src/overlay.rs
+++ b/core/src/overlay.rs
@@ -58,7 +58,7 @@ where
     /// By default, it does nothing.
     fn update(
         &mut self,
-        _event: Event,
+        _event: &Event,
         _layout: Layout<'_>,
         _cursor: mouse::Cursor,
         _renderer: &Renderer,
diff --git a/core/src/overlay/element.rs b/core/src/overlay/element.rs
index 7a179663..de6e73fd 100644
--- a/core/src/overlay/element.rs
+++ b/core/src/overlay/element.rs
@@ -51,7 +51,7 @@ where
     /// Processes a runtime [`Event`].
     pub fn update(
         &mut self,
-        event: Event,
+        event: &Event,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         renderer: &Renderer,
@@ -150,7 +150,7 @@ where
 
     fn update(
         &mut self,
-        event: Event,
+        event: &Event,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         renderer: &Renderer,
diff --git a/core/src/overlay/group.rs b/core/src/overlay/group.rs
index e07744e3..970c1b0e 100644
--- a/core/src/overlay/group.rs
+++ b/core/src/overlay/group.rs
@@ -74,7 +74,7 @@ where
 
     fn update(
         &mut self,
-        event: Event,
+        event: &Event,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         renderer: &Renderer,
@@ -82,14 +82,7 @@ where
         shell: &mut Shell<'_, Message>,
     ) {
         for (child, layout) in self.children.iter_mut().zip(layout.children()) {
-            child.update(
-                event.clone(),
-                layout,
-                cursor,
-                renderer,
-                clipboard,
-                shell,
-            );
+            child.update(event, layout, cursor, renderer, clipboard, shell);
         }
     }
 
diff --git a/core/src/padding.rs b/core/src/padding.rs
index e26cdd9b..9ec02e6d 100644
--- a/core/src/padding.rs
+++ b/core/src/padding.rs
@@ -202,3 +202,9 @@ impl From<Padding> for Size {
         Self::new(padding.horizontal(), padding.vertical())
     }
 }
+
+impl From<Pixels> for Padding {
+    fn from(pixels: Pixels) -> Self {
+        Self::from(pixels.0)
+    }
+}
diff --git a/core/src/pixels.rs b/core/src/pixels.rs
index a1ea0f15..c87e2b31 100644
--- a/core/src/pixels.rs
+++ b/core/src/pixels.rs
@@ -20,9 +20,9 @@ impl From<f32> for Pixels {
     }
 }
 
-impl From<u16> for Pixels {
-    fn from(amount: u16) -> Self {
-        Self(f32::from(amount))
+impl From<u32> for Pixels {
+    fn from(amount: u32) -> Self {
+        Self(amount as f32)
     }
 }
 
@@ -79,3 +79,11 @@ impl std::ops::Div<f32> for Pixels {
         Pixels(self.0 / rhs)
     }
 }
+
+impl std::ops::Div<u32> for Pixels {
+    type Output = Pixels;
+
+    fn div(self, rhs: u32) -> Self {
+        Pixels(self.0 / rhs as f32)
+    }
+}
diff --git a/core/src/shell.rs b/core/src/shell.rs
index 12ebbaa8..56250e2e 100644
--- a/core/src/shell.rs
+++ b/core/src/shell.rs
@@ -1,6 +1,6 @@
 use crate::event;
-use crate::time::Instant;
 use crate::window;
+use crate::InputMethod;
 
 /// A connection to the state of a shell.
 ///
@@ -12,7 +12,8 @@ use crate::window;
 pub struct Shell<'a, Message> {
     messages: &'a mut Vec<Message>,
     event_status: event::Status,
-    redraw_request: Option<window::RedrawRequest>,
+    redraw_request: window::RedrawRequest,
+    input_method: InputMethod,
     is_layout_invalid: bool,
     are_widgets_invalid: bool,
 }
@@ -23,9 +24,10 @@ impl<'a, Message> Shell<'a, Message> {
         Self {
             messages,
             event_status: event::Status::Ignored,
-            redraw_request: None,
+            redraw_request: window::RedrawRequest::Wait,
             is_layout_invalid: false,
             are_widgets_invalid: false,
+            input_method: InputMethod::Disabled,
         }
     }
 
@@ -59,27 +61,55 @@ impl<'a, Message> Shell<'a, Message> {
 
     /// Requests a new frame to be drawn as soon as possible.
     pub fn request_redraw(&mut self) {
-        self.redraw_request = Some(window::RedrawRequest::NextFrame);
-    }
-
-    /// Requests a new frame to be drawn at the given [`Instant`].
-    pub fn request_redraw_at(&mut self, at: Instant) {
-        match self.redraw_request {
-            None => {
-                self.redraw_request = Some(window::RedrawRequest::At(at));
-            }
-            Some(window::RedrawRequest::At(current)) if at < current => {
-                self.redraw_request = Some(window::RedrawRequest::At(at));
-            }
-            _ => {}
-        }
+        self.redraw_request = window::RedrawRequest::NextFrame;
+    }
+
+    /// Requests a new frame to be drawn at the given [`window::RedrawRequest`].
+    pub fn request_redraw_at(
+        &mut self,
+        redraw_request: impl Into<window::RedrawRequest>,
+    ) {
+        self.redraw_request = self.redraw_request.min(redraw_request.into());
     }
 
     /// Returns the request a redraw should happen, if any.
-    pub fn redraw_request(&self) -> Option<window::RedrawRequest> {
+    pub fn redraw_request(&self) -> window::RedrawRequest {
         self.redraw_request
     }
 
+    /// Replaces the redraw request of the [`Shell`]; without conflict resolution.
+    ///
+    /// This is useful if you want to overwrite the redraw request to a previous value.
+    /// Since it's a fairly advanced use case and should rarely be used, it is a static
+    /// method.
+    pub fn replace_redraw_request(
+        shell: &mut Self,
+        redraw_request: window::RedrawRequest,
+    ) {
+        shell.redraw_request = redraw_request;
+    }
+
+    /// Requests the current [`InputMethod`] strategy.
+    ///
+    /// __Important__: This request will only be honored by the
+    /// [`Shell`] only during a [`window::Event::RedrawRequested`].
+    pub fn request_input_method<T: AsRef<str>>(
+        &mut self,
+        ime: &InputMethod<T>,
+    ) {
+        self.input_method.merge(ime);
+    }
+
+    /// Returns the current [`InputMethod`] strategy.
+    pub fn input_method(&self) -> &InputMethod {
+        &self.input_method
+    }
+
+    /// Returns the current [`InputMethod`] strategy.
+    pub fn input_method_mut(&mut self) -> &mut InputMethod {
+        &mut self.input_method
+    }
+
     /// Returns whether the current layout is invalid or not.
     pub fn is_layout_invalid(&self) -> bool {
         self.is_layout_invalid
@@ -122,20 +152,14 @@ impl<'a, Message> Shell<'a, Message> {
     pub fn merge<B>(&mut self, other: Shell<'_, B>, f: impl Fn(B) -> Message) {
         self.messages.extend(other.messages.drain(..).map(f));
 
-        if let Some(new) = other.redraw_request {
-            self.redraw_request = Some(
-                self.redraw_request
-                    .map(|current| if current < new { current } else { new })
-                    .unwrap_or(new),
-            );
-        }
-
         self.is_layout_invalid =
             self.is_layout_invalid || other.is_layout_invalid;
 
         self.are_widgets_invalid =
             self.are_widgets_invalid || other.are_widgets_invalid;
 
+        self.redraw_request = self.redraw_request.min(other.redraw_request);
         self.event_status = self.event_status.merge(other.event_status);
+        self.input_method.merge(&other.input_method);
     }
 }
diff --git a/core/src/text.rs b/core/src/text.rs
index c144fd24..a7e1f281 100644
--- a/core/src/text.rs
+++ b/core/src/text.rs
@@ -284,15 +284,7 @@ impl<'a, Link, Font> Span<'a, Link, Font> {
     pub fn new(fragment: impl IntoFragment<'a>) -> Self {
         Self {
             text: fragment.into_fragment(),
-            size: None,
-            line_height: None,
-            font: None,
-            color: None,
-            highlight: None,
-            link: None,
-            padding: Padding::ZERO,
-            underline: false,
-            strikethrough: false,
+            ..Self::default()
         }
     }
 
@@ -440,6 +432,23 @@ impl<'a, Link, Font> Span<'a, Link, Font> {
     }
 }
 
+impl<Link, Font> Default for Span<'_, Link, Font> {
+    fn default() -> Self {
+        Self {
+            text: Cow::default(),
+            size: None,
+            line_height: None,
+            font: None,
+            color: None,
+            link: None,
+            highlight: None,
+            padding: Padding::default(),
+            underline: false,
+            strikethrough: false,
+        }
+    }
+}
+
 impl<'a, Link, Font> From<&'a str> for Span<'a, Link, Font> {
     fn from(value: &'a str) -> Self {
         Span::new(value)
diff --git a/core/src/text/paragraph.rs b/core/src/text/paragraph.rs
index 924276c3..700c2c75 100644
--- a/core/src/text/paragraph.rs
+++ b/core/src/text/paragraph.rs
@@ -129,6 +129,12 @@ impl<P: Paragraph> Plain<P> {
         self.raw.min_width()
     }
 
+    /// Returns the minimum height that can fit the contents of the
+    /// [`Paragraph`].
+    pub fn min_height(&self) -> f32 {
+        self.raw.min_height()
+    }
+
     /// Returns the cached [`Paragraph`].
     pub fn raw(&self) -> &P {
         &self.raw
diff --git a/core/src/widget.rs b/core/src/widget.rs
index 2a40f823..3c9c50ab 100644
--- a/core/src/widget.rs
+++ b/core/src/widget.rs
@@ -114,7 +114,7 @@ where
     fn update(
         &mut self,
         _state: &mut Tree,
-        _event: Event,
+        _event: &Event,
         _layout: Layout<'_>,
         _cursor: mouse::Cursor,
         _renderer: &Renderer,
diff --git a/core/src/widget/operation/focusable.rs b/core/src/widget/operation/focusable.rs
index 8f66e575..a1327bc1 100644
--- a/core/src/widget/operation/focusable.rs
+++ b/core/src/widget/operation/focusable.rs
@@ -61,6 +61,33 @@ pub fn focus<T>(target: Id) -> impl Operation<T> {
     Focus { target }
 }
 
+/// Produces an [`Operation`] that unfocuses the focused widget.
+pub fn unfocus<T>() -> impl Operation<T> {
+    struct Unfocus;
+
+    impl<T> Operation<T> for Unfocus {
+        fn focusable(
+            &mut self,
+            _id: Option<&Id>,
+            _bounds: Rectangle,
+            state: &mut dyn Focusable,
+        ) {
+            state.unfocus();
+        }
+
+        fn container(
+            &mut self,
+            _id: Option<&Id>,
+            _bounds: Rectangle,
+            operate_on_children: &mut dyn FnMut(&mut dyn Operation<T>),
+        ) {
+            operate_on_children(self);
+        }
+    }
+
+    Unfocus
+}
+
 /// Produces an [`Operation`] that generates a [`Count`] and chains it with the
 /// provided function to build a new [`Operation`].
 pub fn count() -> impl Operation<Count> {
diff --git a/core/src/window/redraw_request.rs b/core/src/window/redraw_request.rs
index b0c000d6..0ae4face 100644
--- a/core/src/window/redraw_request.rs
+++ b/core/src/window/redraw_request.rs
@@ -8,6 +8,15 @@ pub enum RedrawRequest {
 
     /// Redraw at the given time.
     At(Instant),
+
+    /// No redraw is needed.
+    Wait,
+}
+
+impl From<Instant> for RedrawRequest {
+    fn from(time: Instant) -> Self {
+        Self::At(time)
+    }
 }
 
 #[cfg(test)]
@@ -34,5 +43,8 @@ mod tests {
         assert!(RedrawRequest::At(now) <= RedrawRequest::At(now));
         assert!(RedrawRequest::At(now) <= RedrawRequest::At(later));
         assert!(RedrawRequest::At(later) >= RedrawRequest::At(now));
+
+        assert!(RedrawRequest::Wait > RedrawRequest::NextFrame);
+        assert!(RedrawRequest::Wait > RedrawRequest::At(later));
     }
 }