Inline helper functions in `widget` modules

1 files changed, 375 insertions, 432 deletions

diff --git a/widget/src/scrollable.rs b/widget/src/scrollable.rs
index 6cd2048f..9770ce57 100644
--- a/widget/src/scrollable.rs
+++ b/widget/src/scrollable.rs
@@ -269,20 +269,29 @@ where
         renderer: &Renderer,
         limits: &layout::Limits,
     ) -> layout::Node {
-        layout(
-            renderer,
-            limits,
-            self.width,
-            self.height,
-            &self.direction,
-            |renderer, limits| {
-                self.content.as_widget().layout(
-                    &mut tree.children[0],
-                    renderer,
-                    limits,
-                )
-            },
-        )
+        layout::contained(limits, self.width, self.height, |limits| {
+            let child_limits = layout::Limits::new(
+                Size::new(limits.min().width, limits.min().height),
+                Size::new(
+                    if self.direction.horizontal().is_some() {
+                        f32::INFINITY
+                    } else {
+                        limits.max().width
+                    },
+                    if self.direction.vertical().is_some() {
+                        f32::MAX
+                    } else {
+                        limits.max().height
+                    },
+                ),
+            );
+
+            self.content.as_widget().layout(
+                &mut tree.children[0],
+                renderer,
+                &child_limits,
+            )
+        })
     }
 
     fn operate(
@@ -332,28 +341,316 @@ where
         shell: &mut Shell<'_, Message>,
         _viewport: &Rectangle,
     ) -> event::Status {
-        update(
-            tree.state.downcast_mut::<State>(),
-            event,
-            layout,
-            cursor,
-            clipboard,
-            shell,
-            self.direction,
-            &self.on_scroll,
-            |event, layout, cursor, clipboard, shell, viewport| {
-                self.content.as_widget_mut().on_event(
-                    &mut tree.children[0],
-                    event,
-                    layout,
-                    cursor,
-                    renderer,
-                    clipboard,
+        let state = tree.state.downcast_mut::<State>();
+        let bounds = layout.bounds();
+        let cursor_over_scrollable = cursor.position_over(bounds);
+
+        let content = layout.children().next().unwrap();
+        let content_bounds = content.bounds();
+
+        let scrollbars =
+            Scrollbars::new(state, self.direction, bounds, content_bounds);
+
+        let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
+            scrollbars.is_mouse_over(cursor);
+
+        let mut event_status = {
+            let cursor = match cursor_over_scrollable {
+                Some(cursor_position)
+                    if !(mouse_over_x_scrollbar || mouse_over_y_scrollbar) =>
+                {
+                    mouse::Cursor::Available(
+                        cursor_position
+                            + state.translation(
+                                self.direction,
+                                bounds,
+                                content_bounds,
+                            ),
+                    )
+                }
+                _ => mouse::Cursor::Unavailable,
+            };
+
+            let translation =
+                state.translation(self.direction, bounds, content_bounds);
+
+            self.content.as_widget_mut().on_event(
+                &mut tree.children[0],
+                event.clone(),
+                layout,
+                cursor,
+                renderer,
+                clipboard,
+                shell,
+                &Rectangle {
+                    y: bounds.y + translation.y,
+                    x: bounds.x + translation.x,
+                    ..bounds
+                },
+            )
+        };
+
+        if let event::Status::Captured = event_status {
+            return event::Status::Captured;
+        }
+
+        if let Event::Keyboard(keyboard::Event::ModifiersChanged(modifiers)) =
+            event
+        {
+            state.keyboard_modifiers = modifiers;
+
+            return event::Status::Ignored;
+        }
+
+        match event {
+            Event::Mouse(mouse::Event::WheelScrolled { delta }) => {
+                if cursor_over_scrollable.is_none() {
+                    return event::Status::Ignored;
+                }
+
+                let delta = match delta {
+                    mouse::ScrollDelta::Lines { x, y } => {
+                        // TODO: Configurable speed/friction (?)
+                        let movement = if state.keyboard_modifiers.shift() {
+                            Vector::new(y, x)
+                        } else {
+                            Vector::new(x, y)
+                        };
+
+                        movement * 60.0
+                    }
+                    mouse::ScrollDelta::Pixels { x, y } => Vector::new(x, y),
+                };
+
+                state.scroll(delta, self.direction, bounds, content_bounds);
+
+                notify_on_scroll(
+                    state,
+                    &self.on_scroll,
+                    bounds,
+                    content_bounds,
                     shell,
-                    viewport,
-                )
-            },
-        )
+                );
+
+                event_status = event::Status::Captured;
+            }
+            Event::Touch(event)
+                if state.scroll_area_touched_at.is_some()
+                    || !mouse_over_y_scrollbar && !mouse_over_x_scrollbar =>
+            {
+                match event {
+                    touch::Event::FingerPressed { .. } => {
+                        let Some(cursor_position) = cursor.position() else {
+                            return event::Status::Ignored;
+                        };
+
+                        state.scroll_area_touched_at = Some(cursor_position);
+                    }
+                    touch::Event::FingerMoved { .. } => {
+                        if let Some(scroll_box_touched_at) =
+                            state.scroll_area_touched_at
+                        {
+                            let Some(cursor_position) = cursor.position()
+                            else {
+                                return event::Status::Ignored;
+                            };
+
+                            let delta = Vector::new(
+                                cursor_position.x - scroll_box_touched_at.x,
+                                cursor_position.y - scroll_box_touched_at.y,
+                            );
+
+                            state.scroll(
+                                delta,
+                                self.direction,
+                                bounds,
+                                content_bounds,
+                            );
+
+                            state.scroll_area_touched_at =
+                                Some(cursor_position);
+
+                            notify_on_scroll(
+                                state,
+                                &self.on_scroll,
+                                bounds,
+                                content_bounds,
+                                shell,
+                            );
+                        }
+                    }
+                    touch::Event::FingerLifted { .. }
+                    | touch::Event::FingerLost { .. } => {
+                        state.scroll_area_touched_at = None;
+                    }
+                }
+
+                event_status = event::Status::Captured;
+            }
+            _ => {}
+        }
+
+        if let Some(scroller_grabbed_at) = state.y_scroller_grabbed_at {
+            match event {
+                Event::Mouse(mouse::Event::ButtonReleased(
+                    mouse::Button::Left,
+                ))
+                | Event::Touch(touch::Event::FingerLifted { .. })
+                | Event::Touch(touch::Event::FingerLost { .. }) => {
+                    state.y_scroller_grabbed_at = None;
+
+                    event_status = event::Status::Captured;
+                }
+                Event::Mouse(mouse::Event::CursorMoved { .. })
+                | Event::Touch(touch::Event::FingerMoved { .. }) => {
+                    if let Some(scrollbar) = scrollbars.y {
+                        let Some(cursor_position) = cursor.position() else {
+                            return event::Status::Ignored;
+                        };
+
+                        state.scroll_y_to(
+                            scrollbar.scroll_percentage_y(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+
+                        event_status = event::Status::Captured;
+                    }
+                }
+                _ => {}
+            }
+        } else if mouse_over_y_scrollbar {
+            match event {
+                Event::Mouse(mouse::Event::ButtonPressed(
+                    mouse::Button::Left,
+                ))
+                | Event::Touch(touch::Event::FingerPressed { .. }) => {
+                    let Some(cursor_position) = cursor.position() else {
+                        return event::Status::Ignored;
+                    };
+
+                    if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
+                        scrollbars.grab_y_scroller(cursor_position),
+                        scrollbars.y,
+                    ) {
+                        state.scroll_y_to(
+                            scrollbar.scroll_percentage_y(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        state.y_scroller_grabbed_at = Some(scroller_grabbed_at);
+
+                        notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+                    }
+
+                    event_status = event::Status::Captured;
+                }
+                _ => {}
+            }
+        }
+
+        if let Some(scroller_grabbed_at) = state.x_scroller_grabbed_at {
+            match event {
+                Event::Mouse(mouse::Event::ButtonReleased(
+                    mouse::Button::Left,
+                ))
+                | Event::Touch(touch::Event::FingerLifted { .. })
+                | Event::Touch(touch::Event::FingerLost { .. }) => {
+                    state.x_scroller_grabbed_at = None;
+
+                    event_status = event::Status::Captured;
+                }
+                Event::Mouse(mouse::Event::CursorMoved { .. })
+                | Event::Touch(touch::Event::FingerMoved { .. }) => {
+                    let Some(cursor_position) = cursor.position() else {
+                        return event::Status::Ignored;
+                    };
+
+                    if let Some(scrollbar) = scrollbars.x {
+                        state.scroll_x_to(
+                            scrollbar.scroll_percentage_x(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+                    }
+
+                    event_status = event::Status::Captured;
+                }
+                _ => {}
+            }
+        } else if mouse_over_x_scrollbar {
+            match event {
+                Event::Mouse(mouse::Event::ButtonPressed(
+                    mouse::Button::Left,
+                ))
+                | Event::Touch(touch::Event::FingerPressed { .. }) => {
+                    let Some(cursor_position) = cursor.position() else {
+                        return event::Status::Ignored;
+                    };
+
+                    if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
+                        scrollbars.grab_x_scroller(cursor_position),
+                        scrollbars.x,
+                    ) {
+                        state.scroll_x_to(
+                            scrollbar.scroll_percentage_x(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        state.x_scroller_grabbed_at = Some(scroller_grabbed_at);
+
+                        notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+
+                        event_status = event::Status::Captured;
+                    }
+                }
+                _ => {}
+            }
+        }
+
+        event_status
     }
 
     fn draw(
@@ -551,21 +848,48 @@ where
         _viewport: &Rectangle,
         renderer: &Renderer,
     ) -> mouse::Interaction {
-        mouse_interaction(
-            tree.state.downcast_ref::<State>(),
-            layout,
-            cursor,
-            self.direction,
-            |layout, cursor, viewport| {
-                self.content.as_widget().mouse_interaction(
-                    &tree.children[0],
-                    layout,
-                    cursor,
-                    viewport,
-                    renderer,
-                )
-            },
-        )
+        let state = tree.state.downcast_ref::<State>();
+        let bounds = layout.bounds();
+        let cursor_over_scrollable = cursor.position_over(bounds);
+
+        let content_layout = layout.children().next().unwrap();
+        let content_bounds = content_layout.bounds();
+
+        let scrollbars =
+            Scrollbars::new(state, self.direction, bounds, content_bounds);
+
+        let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
+            scrollbars.is_mouse_over(cursor);
+
+        if (mouse_over_x_scrollbar || mouse_over_y_scrollbar)
+            || state.scrollers_grabbed()
+        {
+            mouse::Interaction::Idle
+        } else {
+            let translation =
+                state.translation(self.direction, bounds, content_bounds);
+
+            let cursor = match cursor_over_scrollable {
+                Some(cursor_position)
+                    if !(mouse_over_x_scrollbar || mouse_over_y_scrollbar) =>
+                {
+                    mouse::Cursor::Available(cursor_position + translation)
+                }
+                _ => mouse::Cursor::Unavailable,
+            };
+
+            self.content.as_widget().mouse_interaction(
+                &tree.children[0],
+                layout,
+                cursor,
+                &Rectangle {
+                    y: bounds.y + translation.y,
+                    x: bounds.x + translation.x,
+                    ..bounds
+                },
+                renderer,
+            )
+        }
     }
 
     fn overlay<'b>(
@@ -651,386 +975,6 @@ pub fn scroll_to<Message: 'static>(
     Command::widget(operation::scrollable::scroll_to(id.0, offset))
 }
 
-/// Computes the layout of a [`Scrollable`].
-pub fn layout<Renderer>(
-    renderer: &Renderer,
-    limits: &layout::Limits,
-    width: Length,
-    height: Length,
-    direction: &Direction,
-    layout_content: impl FnOnce(&Renderer, &layout::Limits) -> layout::Node,
-) -> layout::Node {
-    layout::contained(limits, width, height, |limits| {
-        let child_limits = layout::Limits::new(
-            Size::new(limits.min().width, limits.min().height),
-            Size::new(
-                if direction.horizontal().is_some() {
-                    f32::INFINITY
-                } else {
-                    limits.max().width
-                },
-                if direction.vertical().is_some() {
-                    f32::MAX
-                } else {
-                    limits.max().height
-                },
-            ),
-        );
-
-        layout_content(renderer, &child_limits)
-    })
-}
-
-/// Processes an [`Event`] and updates the [`State`] of a [`Scrollable`]
-/// accordingly.
-pub fn update<Message>(
-    state: &mut State,
-    event: Event,
-    layout: Layout<'_>,
-    cursor: mouse::Cursor,
-    clipboard: &mut dyn Clipboard,
-    shell: &mut Shell<'_, Message>,
-    direction: Direction,
-    on_scroll: &Option<Box<dyn Fn(Viewport) -> Message + '_>>,
-    update_content: impl FnOnce(
-        Event,
-        Layout<'_>,
-        mouse::Cursor,
-        &mut dyn Clipboard,
-        &mut Shell<'_, Message>,
-        &Rectangle,
-    ) -> event::Status,
-) -> event::Status {
-    let bounds = layout.bounds();
-    let cursor_over_scrollable = cursor.position_over(bounds);
-
-    let content = layout.children().next().unwrap();
-    let content_bounds = content.bounds();
-
-    let scrollbars = Scrollbars::new(state, direction, bounds, content_bounds);
-
-    let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
-        scrollbars.is_mouse_over(cursor);
-
-    let mut event_status = {
-        let cursor = match cursor_over_scrollable {
-            Some(cursor_position)
-                if !(mouse_over_x_scrollbar || mouse_over_y_scrollbar) =>
-            {
-                mouse::Cursor::Available(
-                    cursor_position
-                        + state.translation(direction, bounds, content_bounds),
-                )
-            }
-            _ => mouse::Cursor::Unavailable,
-        };
-
-        let translation = state.translation(direction, bounds, content_bounds);
-
-        update_content(
-            event.clone(),
-            content,
-            cursor,
-            clipboard,
-            shell,
-            &Rectangle {
-                y: bounds.y + translation.y,
-                x: bounds.x + translation.x,
-                ..bounds
-            },
-        )
-    };
-
-    if let event::Status::Captured = event_status {
-        return event::Status::Captured;
-    }
-
-    if let Event::Keyboard(keyboard::Event::ModifiersChanged(modifiers)) = event
-    {
-        state.keyboard_modifiers = modifiers;
-
-        return event::Status::Ignored;
-    }
-
-    match event {
-        Event::Mouse(mouse::Event::WheelScrolled { delta }) => {
-            if cursor_over_scrollable.is_none() {
-                return event::Status::Ignored;
-            }
-
-            let delta = match delta {
-                mouse::ScrollDelta::Lines { x, y } => {
-                    // TODO: Configurable speed/friction (?)
-                    let movement = if state.keyboard_modifiers.shift() {
-                        Vector::new(y, x)
-                    } else {
-                        Vector::new(x, y)
-                    };
-
-                    movement * 60.0
-                }
-                mouse::ScrollDelta::Pixels { x, y } => Vector::new(x, y),
-            };
-
-            state.scroll(delta, direction, bounds, content_bounds);
-
-            notify_on_scroll(state, on_scroll, bounds, content_bounds, shell);
-
-            event_status = event::Status::Captured;
-        }
-        Event::Touch(event)
-            if state.scroll_area_touched_at.is_some()
-                || !mouse_over_y_scrollbar && !mouse_over_x_scrollbar =>
-        {
-            match event {
-                touch::Event::FingerPressed { .. } => {
-                    let Some(cursor_position) = cursor.position() else {
-                        return event::Status::Ignored;
-                    };
-
-                    state.scroll_area_touched_at = Some(cursor_position);
-                }
-                touch::Event::FingerMoved { .. } => {
-                    if let Some(scroll_box_touched_at) =
-                        state.scroll_area_touched_at
-                    {
-                        let Some(cursor_position) = cursor.position() else {
-                            return event::Status::Ignored;
-                        };
-
-                        let delta = Vector::new(
-                            cursor_position.x - scroll_box_touched_at.x,
-                            cursor_position.y - scroll_box_touched_at.y,
-                        );
-
-                        state.scroll(delta, direction, bounds, content_bounds);
-
-                        state.scroll_area_touched_at = Some(cursor_position);
-
-                        notify_on_scroll(
-                            state,
-                            on_scroll,
-                            bounds,
-                            content_bounds,
-                            shell,
-                        );
-                    }
-                }
-                touch::Event::FingerLifted { .. }
-                | touch::Event::FingerLost { .. } => {
-                    state.scroll_area_touched_at = None;
-                }
-            }
-
-            event_status = event::Status::Captured;
-        }
-        _ => {}
-    }
-
-    if let Some(scroller_grabbed_at) = state.y_scroller_grabbed_at {
-        match event {
-            Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left))
-            | Event::Touch(touch::Event::FingerLifted { .. })
-            | Event::Touch(touch::Event::FingerLost { .. }) => {
-                state.y_scroller_grabbed_at = None;
-
-                event_status = event::Status::Captured;
-            }
-            Event::Mouse(mouse::Event::CursorMoved { .. })
-            | Event::Touch(touch::Event::FingerMoved { .. }) => {
-                if let Some(scrollbar) = scrollbars.y {
-                    let Some(cursor_position) = cursor.position() else {
-                        return event::Status::Ignored;
-                    };
-
-                    state.scroll_y_to(
-                        scrollbar.scroll_percentage_y(
-                            scroller_grabbed_at,
-                            cursor_position,
-                        ),
-                        bounds,
-                        content_bounds,
-                    );
-
-                    notify_on_scroll(
-                        state,
-                        on_scroll,
-                        bounds,
-                        content_bounds,
-                        shell,
-                    );
-
-                    event_status = event::Status::Captured;
-                }
-            }
-            _ => {}
-        }
-    } else if mouse_over_y_scrollbar {
-        match event {
-            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
-            | Event::Touch(touch::Event::FingerPressed { .. }) => {
-                let Some(cursor_position) = cursor.position() else {
-                    return event::Status::Ignored;
-                };
-
-                if let (Some(scroller_grabbed_at), Some(scrollbar)) =
-                    (scrollbars.grab_y_scroller(cursor_position), scrollbars.y)
-                {
-                    state.scroll_y_to(
-                        scrollbar.scroll_percentage_y(
-                            scroller_grabbed_at,
-                            cursor_position,
-                        ),
-                        bounds,
-                        content_bounds,
-                    );
-
-                    state.y_scroller_grabbed_at = Some(scroller_grabbed_at);
-
-                    notify_on_scroll(
-                        state,
-                        on_scroll,
-                        bounds,
-                        content_bounds,
-                        shell,
-                    );
-                }
-
-                event_status = event::Status::Captured;
-            }
-            _ => {}
-        }
-    }
-
-    if let Some(scroller_grabbed_at) = state.x_scroller_grabbed_at {
-        match event {
-            Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left))
-            | Event::Touch(touch::Event::FingerLifted { .. })
-            | Event::Touch(touch::Event::FingerLost { .. }) => {
-                state.x_scroller_grabbed_at = None;
-
-                event_status = event::Status::Captured;
-            }
-            Event::Mouse(mouse::Event::CursorMoved { .. })
-            | Event::Touch(touch::Event::FingerMoved { .. }) => {
-                let Some(cursor_position) = cursor.position() else {
-                    return event::Status::Ignored;
-                };
-
-                if let Some(scrollbar) = scrollbars.x {
-                    state.scroll_x_to(
-                        scrollbar.scroll_percentage_x(
-                            scroller_grabbed_at,
-                            cursor_position,
-                        ),
-                        bounds,
-                        content_bounds,
-                    );
-
-                    notify_on_scroll(
-                        state,
-                        on_scroll,
-                        bounds,
-                        content_bounds,
-                        shell,
-                    );
-                }
-
-                event_status = event::Status::Captured;
-            }
-            _ => {}
-        }
-    } else if mouse_over_x_scrollbar {
-        match event {
-            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
-            | Event::Touch(touch::Event::FingerPressed { .. }) => {
-                let Some(cursor_position) = cursor.position() else {
-                    return event::Status::Ignored;
-                };
-
-                if let (Some(scroller_grabbed_at), Some(scrollbar)) =
-                    (scrollbars.grab_x_scroller(cursor_position), scrollbars.x)
-                {
-                    state.scroll_x_to(
-                        scrollbar.scroll_percentage_x(
-                            scroller_grabbed_at,
-                            cursor_position,
-                        ),
-                        bounds,
-                        content_bounds,
-                    );
-
-                    state.x_scroller_grabbed_at = Some(scroller_grabbed_at);
-
-                    notify_on_scroll(
-                        state,
-                        on_scroll,
-                        bounds,
-                        content_bounds,
-                        shell,
-                    );
-
-                    event_status = event::Status::Captured;
-                }
-            }
-            _ => {}
-        }
-    }
-
-    event_status
-}
-
-/// Computes the current [`mouse::Interaction`] of a [`Scrollable`].
-pub fn mouse_interaction(
-    state: &State,
-    layout: Layout<'_>,
-    cursor: mouse::Cursor,
-    direction: Direction,
-    content_interaction: impl FnOnce(
-        Layout<'_>,
-        mouse::Cursor,
-        &Rectangle,
-    ) -> mouse::Interaction,
-) -> mouse::Interaction {
-    let bounds = layout.bounds();
-    let cursor_over_scrollable = cursor.position_over(bounds);
-
-    let content_layout = layout.children().next().unwrap();
-    let content_bounds = content_layout.bounds();
-
-    let scrollbars = Scrollbars::new(state, direction, bounds, content_bounds);
-
-    let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
-        scrollbars.is_mouse_over(cursor);
-
-    if (mouse_over_x_scrollbar || mouse_over_y_scrollbar)
-        || state.scrollers_grabbed()
-    {
-        mouse::Interaction::Idle
-    } else {
-        let translation = state.translation(direction, bounds, content_bounds);
-
-        let cursor = match cursor_over_scrollable {
-            Some(cursor_position)
-                if !(mouse_over_x_scrollbar || mouse_over_y_scrollbar) =>
-            {
-                mouse::Cursor::Available(cursor_position + translation)
-            }
-            _ => mouse::Cursor::Unavailable,
-        };
-
-        content_interaction(
-            content_layout,
-            cursor,
-            &Rectangle {
-                y: bounds.y + translation.y,
-                x: bounds.x + translation.x,
-                ..bounds
-            },
-        )
-    }
-}
-
 fn notify_on_scroll<Message>(
     state: &mut State,
     on_scroll: &Option<Box<dyn Fn(Viewport) -> Message + '_>>,
@@ -1078,9 +1022,8 @@ fn notify_on_scroll<Message>(
     }
 }
 
-/// The local state of a [`Scrollable`].
 #[derive(Debug, Clone, Copy)]
-pub struct State {
+struct State {
     scroll_area_touched_at: Option<Point>,
     offset_y: Offset,
     y_scroller_grabbed_at: Option<f32>,