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

iced_widget/
pick_list.rs
