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

iced_widget/
pick_list.rs
