iced_widget/
pick_list.rs

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

iced_widget/
pick_list.rs
