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

iced_widget/
pick_list.rs
