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Diffstat (limited to 'native/src/widget/mouse_area.rs')
| -rw-r--r-- | native/src/widget/mouse_area.rs | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/native/src/widget/mouse_area.rs b/native/src/widget/mouse_area.rs new file mode 100644 index 00000000..1b8b318c --- /dev/null +++ b/native/src/widget/mouse_area.rs @@ -0,0 +1,353 @@ +//! A container for capturing mouse events. + +use crate::event::{self, Event}; +use crate::layout; +use crate::mouse; +use crate::overlay; +use crate::renderer; +use crate::touch; +use crate::widget::{tree, Operation, Tree}; +use crate::{ + Clipboard, Element, Layout, Length, Point, Rectangle, Shell, Widget, +}; + +/// Emit messages on mouse events. +#[allow(missing_debug_implementations)] +pub struct MouseArea<'a, Message, Renderer> { + content: Element<'a, Message, Renderer>, + on_press: Option<Message>, + on_release: Option<Message>, + on_right_press: Option<Message>, + on_right_release: Option<Message>, + on_middle_press: Option<Message>, + on_middle_release: Option<Message>, + on_mouse_enter: Option<Message>, + on_mouse_exit: Option<Message>, +} + +impl<'a, Message, Renderer> MouseArea<'a, Message, Renderer> { + /// The message to emit on a left button press. + #[must_use] + pub fn on_press(mut self, message: Message) -> Self { + self.on_press = Some(message); + self + } + + /// The message to emit on a left button release. + #[must_use] + pub fn on_release(mut self, message: Message) -> Self { + self.on_release = Some(message); + self + } + + /// The message to emit on a right button press. + #[must_use] + pub fn on_right_press(mut self, message: Message) -> Self { + self.on_right_press = Some(message); + self + } + + /// The message to emit on a right button release. + #[must_use] + pub fn on_right_release(mut self, message: Message) -> Self { + self.on_right_release = Some(message); + self + } + + /// The message to emit on a middle button press. + #[must_use] + pub fn on_middle_press(mut self, message: Message) -> Self { + self.on_middle_press = Some(message); + self + } + + /// The message to emit on a middle button release. + #[must_use] + pub fn on_middle_release(mut self, message: Message) -> Self { + self.on_middle_release = Some(message); + self + } + + /// The message to emit when the mouse enters the widget. + #[must_use] + pub fn on_mouse_enter(mut self, message: Message) -> Self { + self.on_mouse_enter = Some(message); + self + } + + /// The messsage to emit when the mouse exits the widget. + #[must_use] + pub fn on_mouse_exit(mut self, message: Message) -> Self { + self.on_mouse_exit = Some(message); + self + } +} + +/// Local state of the [`MouseArea`]. +#[derive(Default)] +struct State { + is_hovered: bool, +} + +impl<'a, Message, Renderer> MouseArea<'a, Message, Renderer> { + /// Creates an empty [`MouseArea`]. + pub fn new(content: impl Into<Element<'a, Message, Renderer>>) -> Self { + MouseArea { + content: content.into(), + on_press: None, + on_release: None, + on_right_press: None, + on_right_release: None, + on_middle_press: None, + on_middle_release: None, + on_mouse_enter: None, + on_mouse_exit: None, + } + } +} + +impl<'a, Message, Renderer> Widget<Message, Renderer> + for MouseArea<'a, Message, Renderer> +where + Renderer: crate::Renderer, + Message: Clone, +{ + fn tag(&self) -> tree::Tag { + tree::Tag::of::<State>() + } + + fn state(&self) -> tree::State { + tree::State::new(State::default()) + } + + fn children(&self) -> Vec<Tree> { + vec![Tree::new(&self.content)] + } + + fn diff(&self, tree: &mut Tree) { + tree.diff_children(std::slice::from_ref(&self.content)); + } + + fn width(&self) -> Length { + self.content.as_widget().width() + } + + fn height(&self) -> Length { + self.content.as_widget().height() + } + + fn layout( + &self, + renderer: &Renderer, + limits: &layout::Limits, + ) -> layout::Node { + self.content.as_widget().layout(renderer, limits) + } + + fn operate( + &self, + tree: &mut Tree, + layout: Layout<'_>, + renderer: &Renderer, + operation: &mut dyn Operation<Message>, + ) { + self.content.as_widget().operate( + &mut tree.children[0], + layout, + renderer, + operation, + ); + } + + fn on_event( + &mut self, + tree: &mut Tree, + event: Event, + layout: Layout<'_>, + cursor_position: Point, + renderer: &Renderer, + clipboard: &mut dyn Clipboard, + shell: &mut Shell<'_, Message>, + ) -> event::Status { + if let event::Status::Captured = self.content.as_widget_mut().on_event( + &mut tree.children[0], + event.clone(), + layout, + cursor_position, + renderer, + clipboard, + shell, + ) { + return event::Status::Captured; + } + + update( + self, + &event, + layout, + cursor_position, + shell, + tree.state.downcast_mut::<State>(), + ) + } + + fn mouse_interaction( + &self, + tree: &Tree, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + renderer: &Renderer, + ) -> mouse::Interaction { + self.content.as_widget().mouse_interaction( + &tree.children[0], + layout, + cursor_position, + viewport, + renderer, + ) + } + + fn draw( + &self, + tree: &Tree, + renderer: &mut Renderer, + theme: &Renderer::Theme, + renderer_style: &renderer::Style, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + ) { + self.content.as_widget().draw( + &tree.children[0], + renderer, + theme, + renderer_style, + layout, + cursor_position, + viewport, + ); + } + + fn overlay<'b>( + &'b mut self, + tree: &'b mut Tree, + layout: Layout<'_>, + renderer: &Renderer, + ) -> Option<overlay::Element<'b, Message, Renderer>> { + self.content.as_widget_mut().overlay( + &mut tree.children[0], + layout, + renderer, + ) + } +} + +impl<'a, Message, Renderer> From<MouseArea<'a, Message, Renderer>> + for Element<'a, Message, Renderer> +where + Message: 'a + Clone, + Renderer: 'a + crate::Renderer, +{ + fn from( + area: MouseArea<'a, Message, Renderer>, + ) -> Element<'a, Message, Renderer> { + Element::new(area) + } +} + +/// Processes the given [`Event`] and updates the [`State`] of an [`MouseArea`] +/// accordingly. +fn update<Message: Clone, Renderer>( + widget: &mut MouseArea<'_, Message, Renderer>, + event: &Event, + layout: Layout<'_>, + cursor_position: Point, + shell: &mut Shell<'_, Message>, + state: &mut State, +) -> event::Status { + let was_hovered = state.is_hovered; + + state.is_hovered = layout.bounds().contains(cursor_position); + + if !state.is_hovered { + if was_hovered { + if let Some(message) = widget.on_mouse_exit.as_ref() { + shell.publish(message.clone()); + } + } + + return event::Status::Ignored; + } + + if !was_hovered { + if let Some(message) = widget.on_mouse_enter.as_ref() { + shell.publish(message.clone()); + } + } + + if let Some(message) = widget.on_press.as_ref() { + if let Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left)) + | Event::Touch(touch::Event::FingerPressed { .. }) = event + { + shell.publish(message.clone()); + + return event::Status::Captured; + } + } + + if let Some(message) = widget.on_release.as_ref() { + if let Event::Mouse(mouse::Event::ButtonReleased(mouse::Button::Left)) + | Event::Touch(touch::Event::FingerLifted { .. }) = event + { + shell.publish(message.clone()); + + return event::Status::Captured; + } + } + + if let Some(message) = widget.on_right_press.as_ref() { + if let Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Right)) = + event + { + shell.publish(message.clone()); + + return event::Status::Captured; + } + } + + if let Some(message) = widget.on_right_release.as_ref() { + if let Event::Mouse(mouse::Event::ButtonReleased( + mouse::Button::Right, + )) = event + { + shell.publish(message.clone()); + + return event::Status::Captured; + } + } + + if let Some(message) = widget.on_middle_press.as_ref() { + if let Event::Mouse(mouse::Event::ButtonPressed( + mouse::Button::Middle, + )) = event + { + shell.publish(message.clone()); + + return event::Status::Captured; + } + } + + if let Some(message) = widget.on_middle_release.as_ref() { + if let Event::Mouse(mouse::Event::ButtonReleased( + mouse::Button::Middle, + )) = event + { + shell.publish(message.clone()); + + return event::Status::Captured; + } + } + + event::Status::Ignored +} |