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Diffstat (limited to 'widget/src/tooltip.rs')
| -rw-r--r-- | widget/src/tooltip.rs | 388 |
1 files changed, 388 insertions, 0 deletions
diff --git a/widget/src/tooltip.rs b/widget/src/tooltip.rs new file mode 100644 index 00000000..084650d1 --- /dev/null +++ b/widget/src/tooltip.rs @@ -0,0 +1,388 @@ +//! Display a widget over another. +use crate::container; +use crate::core; +use crate::core::event::{self, Event}; +use crate::core::layout::{self, Layout}; +use crate::core::mouse; +use crate::core::overlay; +use crate::core::renderer; +use crate::core::text; +use crate::core::widget::Tree; +use crate::core::{ + Clipboard, Element, Length, Padding, Pixels, Point, Rectangle, Shell, Size, + Vector, Widget, +}; +use crate::Text; + +use std::borrow::Cow; + +/// An element to display a widget over another. +#[allow(missing_debug_implementations)] +pub struct Tooltip<'a, Message, Renderer = crate::Renderer> +where + Renderer: text::Renderer, + Renderer::Theme: container::StyleSheet + crate::text::StyleSheet, +{ + content: Element<'a, Message, Renderer>, + tooltip: Text<'a, Renderer>, + position: Position, + gap: f32, + padding: f32, + snap_within_viewport: bool, + style: <Renderer::Theme as container::StyleSheet>::Style, +} + +impl<'a, Message, Renderer> Tooltip<'a, Message, Renderer> +where + Renderer: text::Renderer, + Renderer::Theme: container::StyleSheet + crate::text::StyleSheet, +{ + /// The default padding of a [`Tooltip`] drawn by this renderer. + const DEFAULT_PADDING: f32 = 5.0; + + /// Creates a new [`Tooltip`]. + /// + /// [`Tooltip`]: struct.Tooltip.html + pub fn new( + content: impl Into<Element<'a, Message, Renderer>>, + tooltip: impl Into<Cow<'a, str>>, + position: Position, + ) -> Self { + Tooltip { + content: content.into(), + tooltip: Text::new(tooltip), + position, + gap: 0.0, + padding: Self::DEFAULT_PADDING, + snap_within_viewport: true, + style: Default::default(), + } + } + + /// Sets the size of the text of the [`Tooltip`]. + pub fn size(mut self, size: impl Into<Pixels>) -> Self { + self.tooltip = self.tooltip.size(size); + self + } + + /// Sets the font of the [`Tooltip`]. + /// + /// [`Font`]: Renderer::Font + pub fn font(mut self, font: impl Into<Renderer::Font>) -> Self { + self.tooltip = self.tooltip.font(font); + self + } + + /// Sets the gap between the content and its [`Tooltip`]. + pub fn gap(mut self, gap: impl Into<Pixels>) -> Self { + self.gap = gap.into().0; + self + } + + /// Sets the padding of the [`Tooltip`]. + pub fn padding(mut self, padding: impl Into<Pixels>) -> Self { + self.padding = padding.into().0; + self + } + + /// Sets whether the [`Tooltip`] is snapped within the viewport. + pub fn snap_within_viewport(mut self, snap: bool) -> Self { + self.snap_within_viewport = snap; + self + } + + /// Sets the style of the [`Tooltip`]. + pub fn style( + mut self, + style: impl Into<<Renderer::Theme as container::StyleSheet>::Style>, + ) -> Self { + self.style = style.into(); + self + } +} + +impl<'a, Message, Renderer> Widget<Message, Renderer> + for Tooltip<'a, Message, Renderer> +where + Renderer: text::Renderer, + Renderer::Theme: container::StyleSheet + crate::text::StyleSheet, +{ + 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 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 { + self.content.as_widget_mut().on_event( + &mut tree.children[0], + event, + layout, + cursor_position, + renderer, + clipboard, + shell, + ) + } + + 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, + inherited_style: &renderer::Style, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + ) { + self.content.as_widget().draw( + &tree.children[0], + renderer, + theme, + inherited_style, + layout, + cursor_position, + viewport, + ); + + let tooltip = &self.tooltip; + + draw( + renderer, + theme, + inherited_style, + layout, + cursor_position, + viewport, + self.position, + self.gap, + self.padding, + self.snap_within_viewport, + &self.style, + |renderer, limits| { + Widget::<(), Renderer>::layout(tooltip, renderer, limits) + }, + |renderer, defaults, layout, cursor_position, viewport| { + Widget::<(), Renderer>::draw( + tooltip, + &Tree::empty(), + renderer, + theme, + defaults, + 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<Tooltip<'a, Message, Renderer>> + for Element<'a, Message, Renderer> +where + Message: 'a, + Renderer: 'a + text::Renderer, + Renderer::Theme: container::StyleSheet + crate::text::StyleSheet, +{ + fn from( + tooltip: Tooltip<'a, Message, Renderer>, + ) -> Element<'a, Message, Renderer> { + Element::new(tooltip) + } +} + +/// The position of the tooltip. Defaults to following the cursor. +#[derive(Debug, Clone, Copy, PartialEq, Eq)] +pub enum Position { + /// The tooltip will follow the cursor. + FollowCursor, + /// The tooltip will appear on the top of the widget. + Top, + /// The tooltip will appear on the bottom of the widget. + Bottom, + /// The tooltip will appear on the left of the widget. + Left, + /// The tooltip will appear on the right of the widget. + Right, +} + +/// Draws a [`Tooltip`]. +pub fn draw<Renderer>( + renderer: &mut Renderer, + theme: &Renderer::Theme, + inherited_style: &renderer::Style, + layout: Layout<'_>, + cursor_position: Point, + viewport: &Rectangle, + position: Position, + gap: f32, + padding: f32, + snap_within_viewport: bool, + style: &<Renderer::Theme as container::StyleSheet>::Style, + layout_text: impl FnOnce(&Renderer, &layout::Limits) -> layout::Node, + draw_text: impl FnOnce( + &mut Renderer, + &renderer::Style, + Layout<'_>, + Point, + &Rectangle, + ), +) where + Renderer: core::Renderer, + Renderer::Theme: container::StyleSheet, +{ + use container::StyleSheet; + + let bounds = layout.bounds(); + + if bounds.contains(cursor_position) { + let style = theme.appearance(style); + + let defaults = renderer::Style { + text_color: style.text_color.unwrap_or(inherited_style.text_color), + }; + + let text_layout = layout_text( + renderer, + &layout::Limits::new( + Size::ZERO, + snap_within_viewport + .then(|| viewport.size()) + .unwrap_or(Size::INFINITY), + ) + .pad(Padding::new(padding)), + ); + + let text_bounds = text_layout.bounds(); + let x_center = bounds.x + (bounds.width - text_bounds.width) / 2.0; + let y_center = bounds.y + (bounds.height - text_bounds.height) / 2.0; + + let mut tooltip_bounds = { + let offset = match position { + Position::Top => Vector::new( + x_center, + bounds.y - text_bounds.height - gap - padding, + ), + Position::Bottom => Vector::new( + x_center, + bounds.y + bounds.height + gap + padding, + ), + Position::Left => Vector::new( + bounds.x - text_bounds.width - gap - padding, + y_center, + ), + Position::Right => Vector::new( + bounds.x + bounds.width + gap + padding, + y_center, + ), + Position::FollowCursor => Vector::new( + cursor_position.x, + cursor_position.y - text_bounds.height, + ), + }; + + Rectangle { + x: offset.x - padding, + y: offset.y - padding, + width: text_bounds.width + padding * 2.0, + height: text_bounds.height + padding * 2.0, + } + }; + + if snap_within_viewport { + if tooltip_bounds.x < viewport.x { + tooltip_bounds.x = viewport.x; + } else if viewport.x + viewport.width + < tooltip_bounds.x + tooltip_bounds.width + { + tooltip_bounds.x = + viewport.x + viewport.width - tooltip_bounds.width; + } + + if tooltip_bounds.y < viewport.y { + tooltip_bounds.y = viewport.y; + } else if viewport.y + viewport.height + < tooltip_bounds.y + tooltip_bounds.height + { + tooltip_bounds.y = + viewport.y + viewport.height - tooltip_bounds.height; + } + } + + renderer.with_layer(Rectangle::with_size(Size::INFINITY), |renderer| { + container::draw_background(renderer, &style, tooltip_bounds); + + draw_text( + renderer, + &defaults, + Layout::with_offset( + Vector::new( + tooltip_bounds.x + padding, + tooltip_bounds.y + padding, + ), + &text_layout, + ), + cursor_position, + viewport, + ) + }); + } +} |