iced_widget/
pick_list.rs

1//! Pick lists display a dropdown list of selectable options.
2//!
3//! # Example
4//! ```no_run
5//! # mod iced { pub mod widget { pub use iced_widget::*; } pub use iced_widget::Renderer; pub use iced_widget::core::*; }
6//! # use iced::widget::Widget;
7//! #
8//! use iced::widget::pick_list;
9//!
10//! struct State {
11//!    favorite: Option<Fruit>,
12//! }
13//!
14//! #[derive(Debug, Clone, Copy, PartialEq, Eq)]
15//! enum Fruit {
16//!     Apple,
17//!     Orange,
18//!     Strawberry,
19//!     Tomato,
20//! }
21//!
22//! #[derive(Debug, Clone)]
23//! enum Message {
24//!     FruitSelected(Fruit),
25//! }
26//!
27//! fn view(state: &State) -> impl Widget<Message> {
28//!     let fruits = [
29//!         Fruit::Apple,
30//!         Fruit::Orange,
31//!         Fruit::Strawberry,
32//!         Fruit::Tomato,
33//!     ];
34//!
35//!     pick_list(
36//!         state.favorite,
37//!         fruits,
38//!         Fruit::to_string,
39//!     )
40//!     .on_select(Message::FruitSelected)
41//!     .placeholder("Select your favorite fruit...")
42//! }
43//!
44//! fn update(state: &mut State, message: Message) {
45//!     match message {
46//!         Message::FruitSelected(fruit) => {
47//!             state.favorite = Some(fruit);
48//!         }
49//!     }
50//! }
51//!
52//! impl std::fmt::Display for Fruit {
53//!     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
54//!         f.write_str(match self {
55//!             Self::Apple => "Apple",
56//!             Self::Orange => "Orange",
57//!             Self::Strawberry => "Strawberry",
58//!             Self::Tomato => "Tomato",
59//!         })
60//!     }
61//! }
62//! ```
63use crate::core::alignment;
64use crate::core::keyboard;
65use crate::core::layout;
66use crate::core::mouse;
67use crate::core::overlay;
68use crate::core::renderer;
69use crate::core::text::paragraph;
70use crate::core::text::{self, Text};
71use crate::core::touch;
72use crate::core::widget::Meta;
73use crate::core::widget::tree::{self, Tree};
74use crate::core::window;
75use crate::core::{
76    Background, Border, Color, Event, Font, Layout, Length, Padding, Pixels, Point, Rectangle,
77    Shell, Size, Theme, Vector, Widget,
78};
79use crate::overlay::menu::{self, Menu};
80
81use std::borrow::Borrow;
82use std::f32;
83
84/// A widget for selecting a single value from a list of options.
85///
86/// # Example
87/// ```no_run
88/// # mod iced { pub mod widget { pub use iced_widget::*; } pub use iced_widget::Renderer; pub use iced_widget::core::*; }
89/// # use iced::widget::Widget;
90/// #
91/// use iced::widget::pick_list;
92///
93/// struct State {
94///    favorite: Option<Fruit>,
95/// }
96///
97/// #[derive(Debug, Clone, Copy, PartialEq, Eq)]
98/// enum Fruit {
99///     Apple,
100///     Orange,
101///     Strawberry,
102///     Tomato,
103/// }
104///
105/// #[derive(Debug, Clone)]
106/// enum Message {
107///     FruitSelected(Fruit),
108/// }
109///
110/// fn view(state: &State) -> impl Widget<Message> {
111///     let fruits = [
112///         Fruit::Apple,
113///         Fruit::Orange,
114///         Fruit::Strawberry,
115///         Fruit::Tomato,
116///     ];
117///
118///     pick_list(
119///         state.favorite,
120///         fruits,
121///         Fruit::to_string,
122///     )
123///     .on_select(Message::FruitSelected)
124///     .placeholder("Select your favorite fruit...")
125/// }
126///
127/// fn update(state: &mut State, message: Message) {
128///     match message {
129///         Message::FruitSelected(fruit) => {
130///             state.favorite = Some(fruit);
131///         }
132///     }
133/// }
134///
135/// impl std::fmt::Display for Fruit {
136///     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
137///         f.write_str(match self {
138///             Self::Apple => "Apple",
139///             Self::Orange => "Orange",
140///             Self::Strawberry => "Strawberry",
141///             Self::Tomato => "Tomato",
142///         })
143///     }
144/// }
145/// ```
146pub struct PickList<'a, T, L, V, Message, Theme = crate::Theme>
147where
148    T: PartialEq + Clone,
149    L: Borrow<[T]> + 'a,
150    V: Borrow<T> + 'a,
151    Theme: Catalog,
152{
153    options: L,
154    to_string: Box<dyn Fn(&T) -> String + 'a>,
155    on_select: Option<Box<dyn Fn(T) -> Message + 'a>>,
156    on_open: Option<Message>,
157    on_close: Option<Message>,
158    placeholder: Option<String>,
159    selected: Option<V>,
160    width: Length,
161    padding: Padding,
162    text_size: Option<Pixels>,
163    line_height: Option<text::LineHeight>,
164    shaping: text::Shaping,
165    ellipsis: text::Ellipsis,
166    font: Option<Font>,
167    handle: Handle,
168    class: <Theme as Catalog>::Class<'a>,
169    menu_class: <Theme as menu::Catalog>::Class<'a>,
170    last_status: Option<Status>,
171    menu_height: Length,
172}
173
174impl<'a, T, L, V, Message, Theme> PickList<'a, T, L, V, Message, Theme>
175where
176    T: PartialEq + Clone,
177    L: Borrow<[T]> + 'a,
178    V: Borrow<T> + 'a,
179    Message: Clone,
180    Theme: Catalog,
181{
182    /// Creates a new [`PickList`] with the given list of options, the current
183    /// selected value, and the message to produce when an option is selected.
184    pub fn new(selected: Option<V>, options: L, to_string: impl Fn(&T) -> String + 'a) -> Self {
185        Self {
186            to_string: Box::new(to_string),
187            on_select: None,
188            on_open: None,
189            on_close: None,
190            options,
191            placeholder: None,
192            selected,
193            width: Length::Shrink,
194            padding: crate::button::DEFAULT_PADDING,
195            text_size: None,
196            line_height: None,
197            shaping: text::Shaping::default(),
198            ellipsis: text::Ellipsis::End,
199            font: None,
200            handle: Handle::default(),
201            class: <Theme as Catalog>::default(),
202            menu_class: <Theme as Catalog>::default_menu(),
203            last_status: None,
204            menu_height: Length::Shrink,
205        }
206    }
207
208    /// Sets the placeholder of the [`PickList`].
209    pub fn placeholder(mut self, placeholder: impl Into<String>) -> Self {
210        self.placeholder = Some(placeholder.into());
211        self
212    }
213
214    /// Sets the width of the [`PickList`].
215    pub fn width(mut self, width: impl Into<Length>) -> Self {
216        self.width = width.into();
217        self
218    }
219
220    /// Sets the height of the [`Menu`].
221    pub fn menu_height(mut self, menu_height: impl Into<Length>) -> Self {
222        self.menu_height = menu_height.into();
223        self
224    }
225
226    /// Sets the [`Padding`] of the [`PickList`].
227    pub fn padding<P: Into<Padding>>(mut self, padding: P) -> Self {
228        self.padding = padding.into();
229        self
230    }
231
232    /// Sets the text size of the [`PickList`].
233    pub fn text_size(mut self, size: impl Into<Pixels>) -> Self {
234        self.text_size = Some(size.into());
235        self
236    }
237
238    /// Sets the text [`text::LineHeight`] of the [`PickList`].
239    pub fn line_height(mut self, line_height: impl Into<text::LineHeight>) -> Self {
240        self.line_height = Some(line_height.into());
241        self
242    }
243
244    /// Sets the [`text::Shaping`] strategy of the [`PickList`].
245    pub fn shaping(mut self, shaping: text::Shaping) -> Self {
246        self.shaping = shaping;
247        self
248    }
249
250    /// Sets the [`text::Ellipsis`] strategy of the [`PickList`].
251    pub fn ellipsis(mut self, ellipsis: text::Ellipsis) -> Self {
252        self.ellipsis = ellipsis;
253        self
254    }
255
256    /// Sets the font of the [`PickList`].
257    pub fn font(mut self, font: impl Into<Font>) -> Self {
258        self.font = Some(font.into());
259        self
260    }
261
262    /// Sets the [`Handle`] of the [`PickList`].
263    pub fn handle(mut self, handle: Handle) -> Self {
264        self.handle = handle;
265        self
266    }
267
268    /// Sets the message that will be produced when the [`PickList`] selected value changes.
269    pub fn on_select(mut self, on_select: impl Fn(T) -> Message + 'a) -> Self {
270        self.on_select = Some(Box::new(on_select));
271        self
272    }
273
274    /// Sets the message that will be produced when the [`PickList`] is opened.
275    pub fn on_open(mut self, on_open: Message) -> Self {
276        self.on_open = Some(on_open);
277        self
278    }
279
280    /// Sets the message that will be produced when the [`PickList`] is closed.
281    pub fn on_close(mut self, on_close: Message) -> Self {
282        self.on_close = Some(on_close);
283        self
284    }
285
286    /// Sets the style of the [`PickList`].
287    #[must_use]
288    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
289    where
290        <Theme as Catalog>::Class<'a>: From<StyleFn<'a, Theme>>,
291    {
292        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
293        self
294    }
295
296    /// Sets the style of the [`Menu`].
297    #[must_use]
298    pub fn menu_style(mut self, style: impl Fn(&Theme) -> menu::Style + 'a) -> Self
299    where
300        <Theme as menu::Catalog>::Class<'a>: From<menu::StyleFn<'a, Theme>>,
301    {
302        self.menu_class = (Box::new(style) as menu::StyleFn<'a, Theme>).into();
303        self
304    }
305
306    /// Sets the style class of the [`PickList`].
307    #[cfg(feature = "advanced")]
308    #[must_use]
309    pub fn class(mut self, class: impl Into<<Theme as Catalog>::Class<'a>>) -> Self {
310        self.class = class.into();
311        self
312    }
313
314    /// Sets the style class of the [`Menu`].
315    #[cfg(feature = "advanced")]
316    #[must_use]
317    pub fn menu_class(mut self, class: impl Into<<Theme as menu::Catalog>::Class<'a>>) -> Self {
318        self.menu_class = class.into();
319        self
320    }
321}
322
323impl<'a, T, L, V, Message, Theme> Meta for PickList<'a, T, L, V, Message, Theme>
324where
325    T: PartialEq + Clone,
326    L: Borrow<[T]> + 'a,
327    V: Borrow<T> + 'a,
328    Theme: Catalog,
329{
330}
331
332impl<'a, T, L, V, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
333    for PickList<'a, T, L, V, Message, Theme>
334where
335    T: Clone + PartialEq + 'a,
336    L: Borrow<[T]>,
337    V: Borrow<T>,
338    Message: Clone + 'a,
339    Theme: Catalog + 'a,
340    Renderer: text::Renderer + 'a,
341{
342    fn tag(&self) -> tree::Tag {
343        tree::Tag::of::<State<Renderer::Paragraph>>()
344    }
345
346    fn state(&self) -> tree::State {
347        tree::State::new(State::<Renderer::Paragraph>::new())
348    }
349
350    fn size(&self) -> Size<Length> {
351        Size {
352            width: self.width,
353            height: Length::Shrink,
354        }
355    }
356
357    fn layout(&mut self, tree: &mut Tree, renderer: &Renderer, limits: &layout::Limits) {
358        let state = tree.state.downcast_mut::<State<Renderer::Paragraph>>();
359
360        let font = self.font.unwrap_or_else(|| renderer.font());
361        let text_size = self.text_size.unwrap_or_else(|| renderer.text_size());
362        let line_height = self.line_height.unwrap_or_else(|| renderer.line_height());
363        let options = self.options.borrow();
364
365        let option_text = Text {
366            content: "",
367            bounds: Size::new(
368                limits.bounds().width,
369                line_height.to_absolute(text_size).into(),
370            ),
371            size: text_size,
372            line_height,
373            font,
374            align_x: text::Alignment::Default,
375            align_y: alignment::Vertical::Center,
376            shaping: self.shaping,
377            wrapping: text::Wrapping::None,
378            ellipsis: self.ellipsis,
379            hint_factor: renderer.hint_factor(),
380        };
381
382        if let Some(placeholder) = &self.placeholder {
383            let _ = state.placeholder.update(Text {
384                content: placeholder,
385                ..option_text
386            });
387        }
388
389        let max_width = match self.width {
390            Length::Shrink => {
391                state.options.resize_with(options.len(), Default::default);
392
393                for (option, paragraph) in options.iter().zip(state.options.iter_mut()) {
394                    let label = (self.to_string)(option);
395
396                    let _ = paragraph.update(Text {
397                        content: &label,
398                        ..option_text
399                    });
400                }
401
402                let labels_width = state.options.iter().fold(0.0, |width, paragraph| {
403                    f32::max(width, paragraph.min_width())
404                });
405
406                labels_width.max(
407                    self.placeholder
408                        .as_ref()
409                        .map(|_| state.placeholder.min_width())
410                        .unwrap_or(0.0),
411                )
412            }
413            _ => 0.0,
414        };
415
416        let size = {
417            let intrinsic = Size::new(
418                max_width + text_size.0 + self.padding.left,
419                f32::from(line_height.to_absolute(text_size)),
420            );
421
422            limits
423                .width(self.width)
424                .shrink(self.padding)
425                .resolve(self.width, Length::Shrink, intrinsic)
426                .expand(self.padding)
427        };
428
429        tree.size = size;
430    }
431
432    fn update(
433        &mut self,
434        tree: &mut Tree,
435        event: &Event,
436        layout: Layout,
437        cursor: mouse::Cursor,
438        _renderer: &Renderer,
439        shell: &mut Shell<'_, Message>,
440        _viewport: &Rectangle,
441    ) {
442        let state = tree.state.downcast_mut::<State<Renderer::Paragraph>>();
443
444        match event {
445            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
446            | Event::Touch(touch::Event::FingerPressed { .. }) => {
447                if state.is_open {
448                    // Event wasn't processed by overlay, so cursor was clicked either outside its
449                    // bounds or on the drop-down, either way we close the overlay.
450                    state.is_open = false;
451
452                    if let Some(on_close) = &self.on_close {
453                        shell.publish(on_close.clone());
454                    }
455
456                    shell.capture_event();
457                } else if cursor.is_over(layout.bounds()) {
458                    let selected = self.selected.as_ref().map(Borrow::borrow);
459
460                    state.is_open = true;
461                    state.hovered_option = self
462                        .options
463                        .borrow()
464                        .iter()
465                        .position(|option| Some(option) == selected);
466
467                    if let Some(on_open) = &self.on_open {
468                        shell.publish(on_open.clone());
469                    }
470
471                    shell.capture_event();
472                }
473            }
474            Event::Mouse(mouse::Event::WheelScrolled {
475                delta: mouse::ScrollDelta::Lines { y, .. },
476            }) => {
477                let Some(on_select) = &self.on_select else {
478                    return;
479                };
480
481                if state.keyboard_modifiers.command()
482                    && cursor.is_over(layout.bounds())
483                    && !state.is_open
484                {
485                    fn find_next<'a, T: PartialEq>(
486                        selected: &'a T,
487                        mut options: impl Iterator<Item = &'a T>,
488                    ) -> Option<&'a T> {
489                        let _ = options.find(|&option| option == selected);
490
491                        options.next()
492                    }
493
494                    let options = self.options.borrow();
495                    let selected = self.selected.as_ref().map(Borrow::borrow);
496
497                    let next_option = if *y < 0.0 {
498                        if let Some(selected) = selected {
499                            find_next(selected, options.iter())
500                        } else {
501                            options.first()
502                        }
503                    } else if *y > 0.0 {
504                        if let Some(selected) = selected {
505                            find_next(selected, options.iter().rev())
506                        } else {
507                            options.last()
508                        }
509                    } else {
510                        None
511                    };
512
513                    if let Some(next_option) = next_option {
514                        shell.publish(on_select(next_option.clone()));
515                    }
516
517                    shell.capture_event();
518                }
519            }
520            Event::Keyboard(keyboard::Event::ModifiersChanged(modifiers)) => {
521                state.keyboard_modifiers = *modifiers;
522            }
523            _ => {}
524        };
525
526        let status = {
527            let is_hovered = cursor.is_over(layout.bounds());
528
529            if self.on_select.is_none() {
530                Status::Disabled
531            } else if state.is_open {
532                Status::Opened { is_hovered }
533            } else if is_hovered {
534                Status::Hovered
535            } else {
536                Status::Active
537            }
538        };
539
540        if let Event::Window(window::Event::RedrawRequested(_now)) = event {
541            self.last_status = Some(status);
542        } else if self
543            .last_status
544            .is_some_and(|last_status| last_status != status)
545        {
546            shell.request_redraw();
547        }
548    }
549
550    fn mouse_interaction(
551        &self,
552        _tree: &Tree,
553        layout: Layout,
554        cursor: mouse::Cursor,
555        _viewport: &Rectangle,
556        _renderer: &Renderer,
557    ) -> mouse::Interaction {
558        let bounds = layout.bounds();
559        let is_mouse_over = cursor.is_over(bounds);
560
561        if is_mouse_over {
562            if self.on_select.is_some() {
563                mouse::Interaction::Pointer
564            } else {
565                mouse::Interaction::Idle
566            }
567        } else {
568            mouse::Interaction::default()
569        }
570    }
571
572    fn draw(
573        &self,
574        tree: &Tree,
575        renderer: &mut Renderer,
576        theme: &Theme,
577        _style: &renderer::Style,
578        layout: Layout,
579        _cursor: mouse::Cursor,
580        viewport: &Rectangle,
581    ) {
582        let font = self.font.unwrap_or_else(|| renderer.font());
583        let selected = self.selected.as_ref().map(Borrow::borrow);
584        let state = tree.state.downcast_ref::<State<Renderer::Paragraph>>();
585
586        let bounds = layout.bounds();
587
588        let style = Catalog::style(
589            theme,
590            &self.class,
591            self.last_status.unwrap_or(Status::Active),
592        );
593
594        renderer.fill_quad(
595            renderer::Quad {
596                bounds,
597                border: style.border,
598                ..renderer::Quad::default()
599            },
600            style.background,
601        );
602
603        let handle = match &self.handle {
604            Handle::Arrow { size } => Some((
605                Renderer::ICON_FONT,
606                Renderer::ARROW_DOWN_ICON,
607                *size,
608                None,
609                text::Shaping::Basic,
610            )),
611            Handle::Static(Icon {
612                font,
613                code_point,
614                size,
615                line_height,
616                shaping,
617            }) => Some((*font, *code_point, *size, *line_height, *shaping)),
618            Handle::Dynamic { open, closed } => {
619                if state.is_open {
620                    Some((
621                        open.font,
622                        open.code_point,
623                        open.size,
624                        open.line_height,
625                        open.shaping,
626                    ))
627                } else {
628                    Some((
629                        closed.font,
630                        closed.code_point,
631                        closed.size,
632                        closed.line_height,
633                        closed.shaping,
634                    ))
635                }
636            }
637            Handle::None => None,
638        };
639
640        if let Some((font, code_point, size, line_height, shaping)) = handle {
641            let size = size.unwrap_or_else(|| renderer.text_size());
642            let line_height = line_height.unwrap_or_else(|| renderer.line_height());
643
644            renderer.fill_text(
645                Text {
646                    content: code_point.to_string(),
647                    size,
648                    line_height,
649                    font,
650                    bounds: Size::new(bounds.width, f32::from(line_height.to_absolute(size))),
651                    align_x: text::Alignment::Right,
652                    align_y: alignment::Vertical::Center,
653                    shaping,
654                    wrapping: text::Wrapping::None,
655                    ellipsis: text::Ellipsis::None,
656                    hint_factor: None,
657                },
658                Point::new(
659                    bounds.x + bounds.width - self.padding.right,
660                    bounds.center_y(),
661                ),
662                style.handle_color,
663                *viewport,
664            );
665        }
666
667        let label = selected.map(&self.to_string);
668
669        if let Some(label) = label.or_else(|| self.placeholder.clone()) {
670            let text_size = self.text_size.unwrap_or_else(|| renderer.text_size());
671            let line_height = self.line_height.unwrap_or_else(|| renderer.line_height());
672
673            renderer.fill_text(
674                Text {
675                    content: label,
676                    size: text_size,
677                    line_height,
678                    font,
679                    bounds: Size::new(
680                        bounds.width - self.padding.x(),
681                        f32::from(line_height.to_absolute(text_size)),
682                    ),
683                    align_x: text::Alignment::Default,
684                    align_y: alignment::Vertical::Center,
685                    shaping: self.shaping,
686                    wrapping: text::Wrapping::None,
687                    ellipsis: self.ellipsis,
688                    hint_factor: renderer.hint_factor(),
689                },
690                Point::new(bounds.x + self.padding.left, bounds.center_y()),
691                if selected.is_some() {
692                    style.text_color
693                } else {
694                    style.placeholder_color
695                },
696                *viewport,
697            );
698        }
699    }
700
701    fn operate(
702        &mut self,
703        _tree: &mut Tree,
704        layout: Layout,
705        _viewport: &Rectangle,
706        _renderer: &Renderer,
707        operation: &mut dyn crate::core::widget::Operation,
708    ) {
709        let selected = self.selected.as_ref().map(Borrow::borrow);
710        let label = selected.map(&self.to_string);
711
712        if let Some(mut label) = label.or_else(|| self.placeholder.clone()) {
713            operation.text(None, layout.bounds(), &mut label);
714        }
715    }
716
717    fn overlay<'b>(
718        &'b mut self,
719        tree: &'b mut Tree,
720        layout: Layout,
721        renderer: &Renderer,
722        _viewport: &Rectangle,
723        translation: Vector,
724        window: Size,
725    ) -> Vec<overlay::Element<'b, Message, Theme, Renderer>> {
726        let Some(on_select) = &self.on_select else {
727            return Vec::new();
728        };
729
730        let state = tree.state.downcast_mut::<State<Renderer::Paragraph>>();
731        let font = self.font.unwrap_or_else(|| renderer.font());
732
733        if state.is_open {
734            let bounds = layout.bounds();
735            let position = layout.position() + translation;
736
737            let mut menu = Menu::new(
738                &mut state.menu,
739                self.options.borrow(),
740                &mut state.hovered_option,
741                &self.to_string,
742                |option| {
743                    state.is_open = false;
744
745                    (on_select)(option)
746                },
747                None,
748                &self.menu_class,
749            )
750            .width(bounds.width)
751            .height(self.menu_height)
752            .padding(self.padding)
753            .font(font)
754            .ellipsis(self.ellipsis)
755            .shaping(self.shaping);
756
757            if let Some(text_size) = self.text_size {
758                menu = menu.text_size(text_size);
759            }
760
761            vec![menu.overlay(renderer, position, window, bounds.height)]
762        } else {
763            Vec::new()
764        }
765    }
766}
767
768#[derive(Debug)]
769struct State<P: text::Paragraph> {
770    menu: menu::State,
771    keyboard_modifiers: keyboard::Modifiers,
772    is_open: bool,
773    hovered_option: Option<usize>,
774    options: Vec<paragraph::Plain<P>>,
775    placeholder: paragraph::Plain<P>,
776}
777
778impl<P: text::Paragraph> State<P> {
779    /// Creates a new [`State`] for a [`PickList`].
780    fn new() -> Self {
781        Self {
782            menu: menu::State::default(),
783            keyboard_modifiers: keyboard::Modifiers::default(),
784            is_open: bool::default(),
785            hovered_option: Option::default(),
786            options: Vec::new(),
787            placeholder: paragraph::Plain::default(),
788        }
789    }
790}
791
792impl<P: text::Paragraph> Default for State<P> {
793    fn default() -> Self {
794        Self::new()
795    }
796}
797
798/// The handle to the right side of the [`PickList`].
799#[derive(Debug, Clone, PartialEq)]
800pub enum Handle {
801    /// Displays an arrow icon (▼).
802    ///
803    /// This is the default.
804    Arrow {
805        /// Font size of the content.
806        size: Option<Pixels>,
807    },
808    /// A custom static handle.
809    Static(Icon),
810    /// A custom dynamic handle.
811    Dynamic {
812        /// The [`Icon`] used when [`PickList`] is closed.
813        closed: Icon,
814        /// The [`Icon`] used when [`PickList`] is open.
815        open: Icon,
816    },
817    /// No handle will be shown.
818    None,
819}
820
821impl Default for Handle {
822    fn default() -> Self {
823        Self::Arrow { size: None }
824    }
825}
826
827/// The icon of a [`Handle`].
828#[derive(Debug, Clone, PartialEq)]
829pub struct Icon {
830    /// Font that will be used to display the `code_point`,
831    pub font: Font,
832    /// The unicode code point that will be used as the icon.
833    pub code_point: char,
834    /// Font size of the content.
835    pub size: Option<Pixels>,
836    /// Line height of the content.
837    pub line_height: Option<text::LineHeight>,
838    /// The shaping strategy of the icon.
839    pub shaping: text::Shaping,
840}
841
842/// The possible status of a [`PickList`].
843#[derive(Debug, Clone, Copy, PartialEq, Eq)]
844pub enum Status {
845    /// The [`PickList`] can be interacted with.
846    Active,
847    /// The [`PickList`] is being hovered.
848    Hovered,
849    /// The [`PickList`] is open.
850    Opened {
851        /// Whether the [`PickList`] is hovered, while open.
852        is_hovered: bool,
853    },
854    /// The [`PickList`] is disabled.
855    Disabled,
856}
857
858/// The appearance of a pick list.
859#[derive(Debug, Clone, Copy, PartialEq)]
860pub struct Style {
861    /// The text [`Color`] of the pick list.
862    pub text_color: Color,
863    /// The placeholder [`Color`] of the pick list.
864    pub placeholder_color: Color,
865    /// The handle [`Color`] of the pick list.
866    pub handle_color: Color,
867    /// The [`Background`] of the pick list.
868    pub background: Background,
869    /// The [`Border`] of the pick list.
870    pub border: Border,
871}
872
873/// The theme catalog of a [`PickList`].
874pub trait Catalog: menu::Catalog {
875    /// The item class of the [`Catalog`].
876    type Class<'a>;
877
878    /// The default class produced by the [`Catalog`].
879    fn default<'a>() -> <Self as Catalog>::Class<'a>;
880
881    /// The default class for the menu of the [`PickList`].
882    fn default_menu<'a>() -> <Self as menu::Catalog>::Class<'a> {
883        <Self as menu::Catalog>::default()
884    }
885
886    /// The [`Style`] of a class with the given status.
887    fn style(&self, class: &<Self as Catalog>::Class<'_>, status: Status) -> Style;
888}
889
890/// A styling function for a [`PickList`].
891///
892/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
893pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
894
895impl Catalog for Theme {
896    type Class<'a> = StyleFn<'a, Self>;
897
898    fn default<'a>() -> StyleFn<'a, Self> {
899        Box::new(default)
900    }
901
902    fn style(&self, class: &StyleFn<'_, Self>, status: Status) -> Style {
903        class(self, status)
904    }
905}
906
907/// The default style of the field of a [`PickList`].
908pub fn default(theme: &Theme, status: Status) -> Style {
909    let palette = theme.palette();
910
911    let active = Style {
912        text_color: palette.background.weak.text,
913        background: palette.background.weak.color.into(),
914        placeholder_color: palette.secondary.base.color,
915        handle_color: palette.background.weak.text,
916        border: Border {
917            radius: 2.0.into(),
918            width: 1.0,
919            color: palette.background.strong.color,
920        },
921    };
922
923    match status {
924        Status::Active => active,
925        Status::Hovered | Status::Opened { .. } => Style {
926            border: Border {
927                color: palette.primary.strong.color,
928                ..active.border
929            },
930            ..active
931        },
932        Status::Disabled => Style {
933            text_color: palette.background.strongest.color,
934            background: palette.background.weaker.color.into(),
935            placeholder_color: palette.background.strongest.color,
936            handle_color: palette.background.strongest.color,
937            border: Border {
938                color: palette.background.weak.color,
939                ..active.border
940            },
941        },
942    }
943}
iced_widget/pick_list.rs

iced_widget/
pick_list.rs
