cosmic/widget/dropdown/
widget.rs

1// Copyright 2023 System76 <info@system76.com>
2// Copyright 2019 Héctor Ramón, Iced contributors
3// SPDX-License-Identifier: MPL-2.0 AND MIT
4
5use super::Id;
6use super::menu::{self, Menu};
7use crate::widget::icon::{self, Handle};
8use crate::{Element, surface};
9use derive_setters::Setters;
10use iced::window;
11use iced_core::event::{self, Event};
12use iced_core::text::{self, Paragraph, Text};
13use iced_core::widget::tree::{self, Tree};
14use iced_core::{
15    Clipboard, Layout, Length, Padding, Pixels, Rectangle, Shell, Size, Vector, Widget,
16};
17use iced_core::{Shadow, alignment, keyboard, layout, mouse, overlay, renderer, svg, touch};
18use iced_widget::pick_list::{self, Catalog};
19use std::borrow::Cow;
20use std::ffi::OsStr;
21use std::hash::{DefaultHasher, Hash, Hasher};
22use std::sync::atomic::{AtomicBool, Ordering};
23use std::sync::{Arc, LazyLock, Mutex};
24
25pub type DropdownView<Message> = Arc<dyn Fn() -> Element<'static, Message> + Send + Sync>;
26static AUTOSIZE_ID: LazyLock<crate::widget::Id> =
27    LazyLock::new(|| crate::widget::Id::new("cosmic-applet-autosize"));
28
29/// A widget for selecting a single value from a list of selections.
30#[derive(Setters)]
31pub struct Dropdown<'a, S: AsRef<str> + Send + Sync + Clone + 'static, Message, AppMessage>
32where
33    [S]: std::borrow::ToOwned,
34{
35    #[setters(skip)]
36    id: Option<Id>,
37    #[setters(skip)]
38    on_selected: Arc<dyn Fn(usize) -> Message + Send + Sync>,
39    #[setters(skip)]
40    selections: Cow<'a, [S]>,
41    #[setters]
42    icons: Cow<'a, [icon::Handle]>,
43    #[setters(skip)]
44    selected: Option<usize>,
45    #[setters(into)]
46    width: Length,
47    gap: f32,
48    #[setters(into)]
49    padding: Padding,
50    #[setters(strip_option, into)]
51    placeholder: Option<Cow<'a, str>>,
52    #[setters(strip_option)]
53    text_size: Option<f32>,
54    text_line_height: text::LineHeight,
55    #[setters(strip_option)]
56    font: Option<crate::font::Font>,
57    #[setters(skip)]
58    on_surface_action: Option<Arc<dyn Fn(surface::Action) -> Message + Send + Sync + 'static>>,
59    #[setters(skip)]
60    action_map: Option<Arc<dyn Fn(Message) -> AppMessage + 'static + Send + Sync>>,
61    #[setters(strip_option)]
62    window_id: Option<window::Id>,
63    #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
64    positioner: iced_runtime::platform_specific::wayland::popup::SctkPositioner,
65}
66
67impl<'a, S: AsRef<str> + Send + Sync + Clone + 'static, Message: 'static, AppMessage: 'static>
68    Dropdown<'a, S, Message, AppMessage>
69where
70    [S]: std::borrow::ToOwned,
71{
72    /// The default gap.
73    pub const DEFAULT_GAP: f32 = 4.0;
74
75    /// The default padding.
76    pub const DEFAULT_PADDING: Padding = Padding::new(8.0);
77
78    /// Creates a new [`Dropdown`] with the given list of selections, the current
79    /// selected value, and the message to produce when an option is selected.
80    pub fn new(
81        selections: Cow<'a, [S]>,
82        selected: Option<usize>,
83        on_selected: impl Fn(usize) -> Message + 'static + Send + Sync,
84    ) -> Self {
85        Self {
86            id: None,
87            on_selected: Arc::new(on_selected),
88            selections,
89            icons: Cow::Borrowed(&[]),
90            selected,
91            placeholder: None,
92            width: Length::Shrink,
93            gap: Self::DEFAULT_GAP,
94            padding: Self::DEFAULT_PADDING,
95            text_size: None,
96            text_line_height: text::LineHeight::Relative(1.2),
97            font: None,
98            window_id: None,
99            #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
100            positioner: iced_runtime::platform_specific::wayland::popup::SctkPositioner::default(),
101            on_surface_action: None,
102            action_map: None,
103        }
104    }
105
106    #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
107    /// Handle dropdown requests for popup creation.
108    /// Intended to be used with [`crate::app::message::get_popup`]
109    pub fn with_popup<NewAppMessage>(
110        self,
111        parent_id: window::Id,
112        on_surface_action: impl Fn(surface::Action) -> Message + Send + Sync + 'static,
113        action_map: impl Fn(Message) -> NewAppMessage + Send + Sync + 'static,
114    ) -> Dropdown<'a, S, Message, NewAppMessage> {
115        let Self {
116            id,
117            on_selected,
118            selections,
119            icons,
120            selected,
121            placeholder,
122            width,
123            gap,
124            padding,
125            text_size,
126            text_line_height,
127            font,
128            positioner,
129            ..
130        } = self;
131
132        Dropdown::<'a, S, Message, NewAppMessage> {
133            id,
134            on_selected,
135            selections,
136            icons,
137            selected,
138            placeholder,
139            width,
140            gap,
141            padding,
142            text_size,
143            text_line_height,
144            font,
145            on_surface_action: Some(Arc::new(on_surface_action)),
146            action_map: Some(Arc::new(action_map)),
147            window_id: Some(parent_id),
148            positioner,
149        }
150    }
151
152    pub fn id(mut self, id: Id) -> Self {
153        self.id = Some(id);
154        self
155    }
156
157    #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
158    pub fn with_positioner(
159        mut self,
160        positioner: iced_runtime::platform_specific::wayland::popup::SctkPositioner,
161    ) -> Self {
162        self.positioner = positioner;
163        self
164    }
165}
166
167impl<
168    S: AsRef<str> + Send + Sync + Clone + 'static,
169    Message: 'static + Clone,
170    AppMessage: 'static + Clone,
171> Widget<Message, crate::Theme, crate::Renderer> for Dropdown<'_, S, Message, AppMessage>
172where
173    [S]: std::borrow::ToOwned,
174{
175    fn tag(&self) -> tree::Tag {
176        tree::Tag::of::<State>()
177    }
178
179    fn state(&self) -> tree::State {
180        tree::State::new(State::new())
181    }
182
183    fn diff(&mut self, tree: &mut Tree) {
184        let state = tree.state.downcast_mut::<State>();
185
186        let mut selections_changed = state.selections.len() != self.selections.len();
187
188        state
189            .selections
190            .resize_with(self.selections.len(), crate::Plain::default);
191        state.hashes.resize(self.selections.len(), 0);
192
193        for (i, selection) in self.selections.iter().enumerate() {
194            let mut hasher = DefaultHasher::new();
195            selection.as_ref().hash(&mut hasher);
196            let text_hash = hasher.finish();
197
198            if state.hashes[i] == text_hash {
199                continue;
200            }
201
202            selections_changed = true;
203            state.hashes[i] = text_hash;
204            state.selections[i].update(Text {
205                content: selection.as_ref(),
206                bounds: Size::INFINITE,
207                // TODO use the renderer default size
208                size: iced::Pixels(self.text_size.unwrap_or(14.0)),
209                line_height: self.text_line_height,
210                font: self.font.unwrap_or_else(crate::font::default),
211                align_x: text::Alignment::Left,
212                align_y: alignment::Vertical::Top,
213                shaping: text::Shaping::Advanced,
214                wrapping: text::Wrapping::default(),
215                ellipsize: text::Ellipsize::default(),
216            });
217        }
218
219        if state.is_open.load(Ordering::SeqCst) && selections_changed {
220            state.close_operation = true;
221            state.open_operation = true;
222        }
223    }
224
225    fn size(&self) -> Size<Length> {
226        Size::new(self.width, Length::Shrink)
227    }
228
229    fn layout(
230        &mut self,
231        tree: &mut Tree,
232        renderer: &crate::Renderer,
233        limits: &layout::Limits,
234    ) -> layout::Node {
235        layout(
236            renderer,
237            limits,
238            self.width,
239            self.gap,
240            self.padding,
241            self.text_size.unwrap_or(14.0),
242            self.text_line_height,
243            self.font,
244            self.selected.and_then(|id| {
245                self.selections
246                    .get(id)
247                    .map(AsRef::as_ref)
248                    .zip(tree.state.downcast_mut::<State>().selections.get_mut(id))
249            }),
250            self.placeholder.as_deref(),
251            !self.icons.is_empty(),
252        )
253    }
254
255    fn update(
256        &mut self,
257        tree: &mut Tree,
258        event: &Event,
259        layout: Layout<'_>,
260        cursor: mouse::Cursor,
261        _renderer: &crate::Renderer,
262        _clipboard: &mut dyn Clipboard,
263        shell: &mut Shell<'_, Message>,
264        _viewport: &Rectangle,
265    ) {
266        update::<S, Message, AppMessage>(
267            &event,
268            layout,
269            cursor,
270            shell,
271            #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
272            self.positioner.clone(),
273            self.on_selected.clone(),
274            self.selected,
275            &self.selections,
276            || tree.state.downcast_mut::<State>(),
277            self.window_id,
278            self.on_surface_action.clone(),
279            self.action_map.clone(),
280            &self.icons,
281            self.gap,
282            self.padding,
283            self.text_size,
284            self.font,
285            self.selected,
286        )
287    }
288
289    fn mouse_interaction(
290        &self,
291        _tree: &Tree,
292        layout: Layout<'_>,
293        cursor: mouse::Cursor,
294        _viewport: &Rectangle,
295        _renderer: &crate::Renderer,
296    ) -> mouse::Interaction {
297        mouse_interaction(layout, cursor)
298    }
299
300    fn draw(
301        &self,
302        tree: &Tree,
303        renderer: &mut crate::Renderer,
304        theme: &crate::Theme,
305        _style: &iced_core::renderer::Style,
306        layout: Layout<'_>,
307        cursor: mouse::Cursor,
308        viewport: &Rectangle,
309    ) {
310        let font = self.font.unwrap_or_else(crate::font::default);
311        draw(
312            renderer,
313            theme,
314            layout,
315            cursor,
316            self.gap,
317            self.padding,
318            self.text_size,
319            self.text_line_height,
320            font,
321            self.selected.and_then(|id| self.selections.get(id)),
322            self.selected.and_then(|id| self.icons.get(id)),
323            self.placeholder.as_deref(),
324            tree.state.downcast_ref::<State>(),
325            viewport,
326        );
327    }
328
329    fn operate(
330        &mut self,
331        tree: &mut Tree,
332        _layout: Layout<'_>,
333        _renderer: &crate::Renderer,
334        operation: &mut dyn iced_core::widget::Operation,
335    ) {
336        // TODO: double check operation handling
337        // let state = tree.state.downcast_mut::<State>();
338        // operation.custom(state, self.id.as_ref());
339    }
340
341    fn overlay<'b>(
342        &'b mut self,
343        tree: &'b mut Tree,
344        layout: Layout<'b>,
345        renderer: &crate::Renderer,
346        viewport: &Rectangle,
347        translation: Vector,
348    ) -> Option<overlay::Element<'b, Message, crate::Theme, crate::Renderer>> {
349        #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
350        if self.window_id.is_some() || self.on_surface_action.is_some() {
351            return None;
352        }
353
354        let state = tree.state.downcast_mut::<State>();
355
356        overlay(
357            layout,
358            renderer,
359            state,
360            self.gap,
361            self.padding,
362            self.text_size.unwrap_or(14.0),
363            self.text_line_height,
364            self.font,
365            &self.selections,
366            &self.icons,
367            self.selected,
368            self.on_selected.as_ref(),
369            translation,
370            None,
371        )
372    }
373
374    // #[cfg(feature = "a11y")]
375    // /// get the a11y nodes for the widget
376    // fn a11y_nodes(
377    //     &self,
378    //     layout: Layout<'_>,
379    //     state: &Tree,
380    //     p: mouse::Cursor,
381    // ) -> iced_accessibility::A11yTree {
382    //     // TODO
383    // }
384}
385
386impl<
387    'a,
388    S: AsRef<str> + Send + Sync + Clone + 'static,
389    Message: 'static + std::clone::Clone,
390    AppMessage: 'static + std::clone::Clone,
391> From<Dropdown<'a, S, Message, AppMessage>> for crate::Element<'a, Message>
392where
393    [S]: std::borrow::ToOwned,
394{
395    fn from(pick_list: Dropdown<'a, S, Message, AppMessage>) -> Self {
396        Self::new(pick_list)
397    }
398}
399
400/// The local state of a [`Dropdown`].
401#[derive(Debug, Clone)]
402pub struct State {
403    icon: Option<svg::Handle>,
404    menu: menu::State,
405    keyboard_modifiers: keyboard::Modifiers,
406    is_open: Arc<AtomicBool>,
407    close_operation: bool,
408    open_operation: bool,
409    hovered_option: Arc<Mutex<Option<usize>>>,
410    hashes: Vec<u64>,
411    selections: Vec<crate::Plain>,
412    popup_id: window::Id,
413}
414
415impl State {
416    /// Creates a new [`State`] for a [`Dropdown`].
417    pub fn new() -> Self {
418        Self {
419            icon: match icon::from_name("pan-down-symbolic").size(16).handle().data {
420                icon::Data::Svg(handle) => Some(handle),
421                icon::Data::Image(_) => None,
422            },
423            menu: menu::State::default(),
424            keyboard_modifiers: keyboard::Modifiers::default(),
425            is_open: Arc::new(AtomicBool::new(false)),
426            hovered_option: Arc::new(Mutex::new(None)),
427            selections: Vec::new(),
428            hashes: Vec::new(),
429            popup_id: window::Id::unique(),
430            close_operation: false,
431            open_operation: false,
432        }
433    }
434}
435
436impl Default for State {
437    fn default() -> Self {
438        Self::new()
439    }
440}
441
442impl super::operation::Dropdown for State {
443    fn close(&mut self) {
444        self.close_operation = true;
445    }
446
447    fn open(&mut self) {
448        self.open_operation = true;
449    }
450}
451
452/// Computes the layout of a [`Dropdown`].
453#[allow(clippy::too_many_arguments)]
454pub fn layout(
455    renderer: &crate::Renderer,
456    limits: &layout::Limits,
457    width: Length,
458    gap: f32,
459    padding: Padding,
460    text_size: f32,
461    text_line_height: text::LineHeight,
462    font: Option<crate::font::Font>,
463    selection: Option<(&str, &mut crate::Plain)>,
464    placeholder: Option<&str>,
465    has_icons: bool,
466) -> layout::Node {
467    use std::f32;
468
469    let limits = limits.width(width).height(Length::Shrink).shrink(padding);
470
471    let max_width = match width {
472        Length::Shrink => {
473            let measure = move |(label, paragraph): (_, Option<&mut crate::Plain>)| -> f32 {
474                let paragraph = match paragraph {
475                    Some(p) => {
476                        let text = Text {
477                            content: label,
478                            bounds: Size::new(f32::MAX, f32::MAX),
479                            size: iced::Pixels(text_size),
480                            line_height: text_line_height,
481                            font: font.unwrap_or_else(crate::font::default),
482                            align_x: text::Alignment::Left,
483                            align_y: alignment::Vertical::Top,
484                            shaping: text::Shaping::Advanced,
485                            wrapping: text::Wrapping::default(),
486                            ellipsize: text::Ellipsize::default(),
487                        };
488                        p.update(text);
489                        p
490                    }
491                    None => {
492                        let text = Text {
493                            content: label.to_string(),
494                            bounds: Size::new(f32::MAX, f32::MAX),
495                            size: iced::Pixels(text_size),
496                            line_height: text_line_height,
497                            font: font.unwrap_or_else(crate::font::default),
498                            align_x: text::Alignment::Left,
499                            align_y: alignment::Vertical::Top,
500                            shaping: text::Shaping::Advanced,
501                            wrapping: text::Wrapping::default(),
502                            ellipsize: text::Ellipsize::default(),
503                        };
504                        &mut crate::Plain::new(text)
505                    }
506                };
507                paragraph.min_width().round()
508            };
509
510            selection
511                .map(|(l, p)| (l, Some(p)))
512                .or_else(|| placeholder.map(|l| (l, None)))
513                .map(measure)
514                .unwrap_or_default()
515        }
516        _ => 0.0,
517    };
518
519    let icon_size = if has_icons { 24.0 } else { 0.0 };
520
521    let size = {
522        let intrinsic = Size::new(
523            max_width + icon_size + gap + 16.0,
524            f32::from(text_line_height.to_absolute(Pixels(text_size))),
525        );
526
527        limits
528            .resolve(width, Length::Shrink, intrinsic)
529            .expand(padding)
530    };
531
532    layout::Node::new(size)
533}
534
535/// Processes an [`Event`] and updates the [`State`] of a [`Dropdown`]
536/// accordingly.
537#[allow(clippy::too_many_arguments, clippy::too_many_lines)]
538pub fn update<
539    'a,
540    S: AsRef<str> + Send + Sync + Clone + 'static,
541    Message: Clone + 'static,
542    AppMessage: Clone + 'static,
543>(
544    event: &Event,
545    layout: Layout<'_>,
546    cursor: mouse::Cursor,
547    shell: &mut Shell<'_, Message>,
548    #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
549    positioner: iced_runtime::platform_specific::wayland::popup::SctkPositioner,
550    on_selected: Arc<dyn Fn(usize) -> Message + Send + Sync + 'static>,
551    selected: Option<usize>,
552    selections: &[S],
553    state: impl FnOnce() -> &'a mut State,
554    _window_id: Option<window::Id>,
555    on_surface_action: Option<Arc<dyn Fn(surface::Action) -> Message + Send + Sync + 'static>>,
556    action_map: Option<Arc<dyn Fn(Message) -> AppMessage + Send + Sync + 'static>>,
557    icons: &[icon::Handle],
558    gap: f32,
559    padding: Padding,
560    text_size: Option<f32>,
561    font: Option<crate::font::Font>,
562    selected_option: Option<usize>,
563) {
564    let state = state();
565
566    let open = |shell: &mut Shell<'_, Message>,
567                state: &mut State,
568                on_selected: Arc<dyn Fn(usize) -> Message + Send + Sync + 'static>| {
569        state.is_open.store(true, Ordering::Relaxed);
570        let mut hovered_guard = state.hovered_option.lock().unwrap();
571        *hovered_guard = selected;
572        let id = window::Id::unique();
573        state.popup_id = id;
574        #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
575        if let Some(((on_surface_action, parent), action_map)) = on_surface_action
576            .as_ref()
577            .zip(_window_id)
578            .zip(action_map.clone())
579        {
580            use iced_runtime::platform_specific::wayland::popup::{
581                SctkPopupSettings, SctkPositioner,
582            };
583            let bounds = layout.bounds();
584            let anchor_rect = Rectangle {
585                x: bounds.x as i32,
586                y: bounds.y as i32,
587                width: bounds.width as i32,
588                height: bounds.height as i32,
589            };
590            let icon_width = if icons.is_empty() { 0.0 } else { 24.0 };
591            let measure = |_label: &str, selection_paragraph: &crate::Paragraph| -> f32 {
592                selection_paragraph.min_width().round()
593            };
594            let pad_width = padding.x().mul_add(2.0, 16.0);
595
596            let selections_width = selections
597                .iter()
598                .zip(state.selections.iter_mut())
599                .map(|(label, selection)| measure(label.as_ref(), selection.raw()))
600                .fold(0.0, |next, current| current.max(next));
601
602            let icons: Cow<'static, [Handle]> = Cow::Owned(icons.to_vec());
603            let selections: Cow<'static, [S]> = Cow::Owned(selections.to_vec());
604            let state = state.clone();
605            let on_close = surface::action::destroy_popup(id);
606            let on_surface_action_clone = on_surface_action.clone();
607            let translation = layout.virtual_offset();
608            let get_popup_action = surface::action::simple_popup::<AppMessage>(
609                move || {
610                    SctkPopupSettings {
611                parent,
612                id,
613                input_zone: None,
614                positioner: SctkPositioner {
615                    size: Some((selections_width as u32 + gap as u32 + pad_width as u32 + icon_width as u32, 10)),
616                    anchor_rect,
617                    // TODO: left or right alignment based on direction?
618                    anchor: cctk::wayland_protocols::xdg::shell::client::xdg_positioner::Anchor::BottomLeft,
619                    gravity: cctk::wayland_protocols::xdg::shell::client::xdg_positioner::Gravity::BottomRight,
620                    reactive: true,
621                    offset: ((-padding.left - translation.x) as i32, -translation.y as i32),
622                    constraint_adjustment: 9,
623                    ..Default::default()
624                },
625                parent_size: None,
626                grab: true,
627                close_with_children: true,
628            }
629                },
630                Some(Box::new(move || {
631                    let action_map = action_map.clone();
632                    let on_selected = on_selected.clone();
633                    let e: Element<'static, crate::Action<AppMessage>> =
634                        Element::from(menu_widget(
635                            bounds,
636                            &state,
637                            gap,
638                            padding,
639                            text_size.unwrap_or(14.0),
640                            selections.clone(),
641                            icons.clone(),
642                            selected_option,
643                            Arc::new(move |i| on_selected.clone()(i)),
644                            Some(on_surface_action_clone(on_close.clone())),
645                        ))
646                        .map(move |m| crate::Action::App(action_map.clone()(m)));
647                    e
648                })),
649            );
650            shell.publish(on_surface_action(get_popup_action));
651        }
652    };
653
654    let is_open = state.is_open.load(Ordering::Relaxed);
655    let refresh = state.close_operation && state.open_operation;
656
657    if state.close_operation {
658        state.close_operation = false;
659        state.is_open.store(false, Ordering::SeqCst);
660        if is_open {
661            #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
662            if let Some(ref on_close) = on_surface_action {
663                shell.publish(on_close(surface::action::destroy_popup(state.popup_id)));
664            }
665        }
666    }
667
668    if state.open_operation {
669        state.open_operation = false;
670        state.is_open.store(true, Ordering::SeqCst);
671        if (refresh && is_open) || (!refresh && !is_open) {
672            open(shell, state, on_selected.clone());
673        }
674    }
675
676    match event {
677        Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
678        | Event::Touch(touch::Event::FingerPressed { .. }) => {
679            let is_open = state.is_open.load(Ordering::Relaxed);
680            if is_open {
681                // Event wasn't processed by overlay, so cursor was clicked either outside it's
682                // bounds or on the drop-down, either way we close the overlay.
683                state.is_open.store(false, Ordering::Relaxed);
684                #[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
685                if let Some(on_close) = on_surface_action {
686                    shell.publish(on_close(surface::action::destroy_popup(state.popup_id)));
687                }
688                shell.capture_event();
689            } else if cursor.is_over(layout.bounds()) {
690                open(shell, state, on_selected);
691                shell.capture_event();
692            }
693        }
694        Event::Mouse(mouse::Event::WheelScrolled {
695            delta: mouse::ScrollDelta::Lines { .. },
696        }) => {
697            let is_open = state.is_open.load(Ordering::Relaxed);
698
699            if state.keyboard_modifiers.command() && cursor.is_over(layout.bounds()) && !is_open {
700                let next_index = selected.map(|index| index + 1).unwrap_or_default();
701
702                if selections.len() < next_index {
703                    shell.publish((on_selected)(next_index));
704                }
705
706                shell.capture_event();
707            }
708        }
709        Event::Keyboard(keyboard::Event::ModifiersChanged(modifiers)) => {
710            state.keyboard_modifiers = *modifiers;
711        }
712        _ => {}
713    }
714}
715
716/// Returns the current [`mouse::Interaction`] of a [`Dropdown`].
717#[must_use]
718pub fn mouse_interaction(layout: Layout<'_>, cursor: mouse::Cursor) -> mouse::Interaction {
719    let bounds = layout.bounds();
720    let is_mouse_over = cursor.is_over(bounds);
721
722    if is_mouse_over {
723        mouse::Interaction::Pointer
724    } else {
725        mouse::Interaction::default()
726    }
727}
728
729#[cfg(all(feature = "winit", feature = "wayland", target_os = "linux"))]
730/// Returns the current menu widget of a [`Dropdown`].
731#[allow(clippy::too_many_arguments)]
732pub fn menu_widget<
733    S: AsRef<str> + Send + Sync + Clone + 'static,
734    Message: 'static + std::clone::Clone,
735>(
736    bounds: Rectangle,
737    state: &State,
738    gap: f32,
739    padding: Padding,
740    text_size: f32,
741    selections: Cow<'static, [S]>,
742    icons: Cow<'static, [icon::Handle]>,
743    selected_option: Option<usize>,
744    on_selected: Arc<dyn Fn(usize) -> Message + Send + Sync + 'static>,
745    close_on_selected: Option<Message>,
746) -> crate::Element<'static, Message>
747where
748    [S]: std::borrow::ToOwned,
749{
750    let icon_width = if icons.is_empty() { 0.0 } else { 24.0 };
751    let measure = |_label: &str, selection_paragraph: &crate::Paragraph| -> f32 {
752        selection_paragraph.min_width().round()
753    };
754    let selections_width = selections
755        .iter()
756        .zip(state.selections.iter())
757        .map(|(label, selection)| measure(label.as_ref(), selection.raw()))
758        .fold(0.0, |next, current| current.max(next));
759    let pad_width = padding.x().mul_add(2.0, 16.0);
760
761    let width = selections_width + gap + pad_width + icon_width;
762    let is_open = state.is_open.clone();
763    let menu: Menu<'static, S, Message> = Menu::new(
764        state.menu.clone(),
765        selections,
766        icons,
767        state.hovered_option.clone(),
768        selected_option,
769        move |option| {
770            is_open.store(false, Ordering::Relaxed);
771
772            (on_selected)(option)
773        },
774        None,
775        close_on_selected,
776    )
777    .width(width)
778    .padding(padding)
779    .text_size(text_size);
780
781    crate::widget::autosize::autosize(
782        menu.popup(iced::Point::new(0., 0.), bounds.height),
783        AUTOSIZE_ID.clone(),
784    )
785    .auto_height(true)
786    .auto_width(true)
787    .min_height(1.)
788    .min_width(width)
789    .into()
790}
791
792/// Returns the current overlay of a [`Dropdown`].
793#[allow(clippy::too_many_arguments)]
794pub fn overlay<'a, S: AsRef<str> + Send + Sync + Clone + 'static, Message: std::clone::Clone + 'a>(
795    layout: Layout<'_>,
796    _renderer: &crate::Renderer,
797    state: &'a mut State,
798    gap: f32,
799    padding: Padding,
800    text_size: f32,
801    _text_line_height: text::LineHeight,
802    _font: Option<crate::font::Font>,
803    selections: &'a [S],
804    icons: &'a [icon::Handle],
805    selected_option: Option<usize>,
806    on_selected: &'a dyn Fn(usize) -> Message,
807    translation: Vector,
808    close_on_selected: Option<Message>,
809) -> Option<overlay::Element<'a, Message, crate::Theme, crate::Renderer>>
810where
811    [S]: std::borrow::ToOwned,
812{
813    if state.is_open.load(Ordering::Relaxed) {
814        let bounds = layout.bounds();
815
816        let menu = Menu::new(
817            state.menu.clone(),
818            Cow::Borrowed(selections),
819            Cow::Borrowed(icons),
820            state.hovered_option.clone(),
821            selected_option,
822            |option| {
823                state.is_open.store(false, Ordering::Relaxed);
824
825                (on_selected)(option)
826            },
827            None,
828            close_on_selected,
829        )
830        .width({
831            let measure = |_label: &str, selection_paragraph: &crate::Paragraph| -> f32 {
832                selection_paragraph.min_width().round()
833            };
834
835            let pad_width = padding.x().mul_add(2.0, 16.0);
836
837            let icon_width = if icons.is_empty() { 0.0 } else { 24.0 };
838
839            selections
840                .iter()
841                .zip(state.selections.iter_mut())
842                .map(|(label, selection)| measure(label.as_ref(), selection.raw()))
843                .fold(0.0, |next, current| current.max(next))
844                + gap
845                + pad_width
846                + icon_width
847        })
848        .padding(padding)
849        .text_size(text_size);
850
851        let mut position = layout.position();
852        position.x -= padding.left;
853        position.x += translation.x;
854        position.y += translation.y;
855        Some(menu.overlay(position, bounds.height))
856    } else {
857        None
858    }
859}
860
861/// Draws a [`Dropdown`].
862#[allow(clippy::too_many_arguments)]
863pub fn draw<'a, S>(
864    renderer: &mut crate::Renderer,
865    theme: &crate::Theme,
866    layout: Layout<'_>,
867    cursor: mouse::Cursor,
868    gap: f32,
869    padding: Padding,
870    text_size: Option<f32>,
871    text_line_height: text::LineHeight,
872    font: crate::font::Font,
873    selected: Option<&'a S>,
874    icon: Option<&'a icon::Handle>,
875    placeholder: Option<&'a str>,
876    state: &'a State,
877    viewport: &Rectangle,
878) where
879    S: AsRef<str> + 'a,
880{
881    let bounds = layout.bounds();
882    let is_mouse_over = cursor.is_over(bounds);
883
884    let style = if is_mouse_over {
885        theme.style(&(), pick_list::Status::Hovered)
886    } else {
887        theme.style(&(), pick_list::Status::Active)
888    };
889
890    iced_core::Renderer::fill_quad(
891        renderer,
892        renderer::Quad {
893            bounds,
894            border: style.border,
895            shadow: Shadow::default(),
896            snap: true,
897        },
898        style.background,
899    );
900
901    if let Some(handle) = state.icon.clone() {
902        let svg_handle = svg::Svg::new(handle).color(style.text_color);
903        let bounds = Rectangle {
904            x: bounds.x + bounds.width - gap - 16.0,
905            y: bounds.center_y() - 8.0,
906            width: 16.0,
907            height: 16.0,
908        };
909        svg::Renderer::draw_svg(renderer, svg_handle, bounds, bounds);
910    }
911
912    if let Some(content) = selected.map(AsRef::as_ref).or(placeholder) {
913        let text_size = text_size.unwrap_or_else(|| text::Renderer::default_size(renderer).0);
914
915        let mut bounds = Rectangle {
916            x: bounds.x + padding.left,
917            y: bounds.center_y(),
918            width: bounds.width - padding.x(),
919            height: f32::from(text_line_height.to_absolute(Pixels(text_size))),
920        };
921
922        if let Some(handle) = icon {
923            let icon_bounds = Rectangle {
924                x: bounds.x,
925                y: bounds.y - (bounds.height / 2.0) - 2.0,
926                width: 20.0,
927                height: 20.0,
928            };
929
930            bounds.x += 24.0;
931            icon::draw(renderer, handle, icon_bounds);
932        }
933
934        text::Renderer::fill_text(
935            renderer,
936            Text {
937                content: content.to_string(),
938                size: iced::Pixels(text_size),
939                line_height: text_line_height,
940                font,
941                bounds: bounds.size(),
942                align_x: text::Alignment::Left,
943                align_y: alignment::Vertical::Center,
944                shaping: text::Shaping::Advanced,
945                wrapping: text::Wrapping::default(),
946                ellipsize: text::Ellipsize::default(),
947            },
948            bounds.position(),
949            style.text_color,
950            *viewport,
951        );
952    }
953}
cosmic/widget/dropdown/widget.rs

cosmic/widget/dropdown/
widget.rs
