iced_widget/
pick_list.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
//! Pick lists display a dropdown list of selectable options.
//!
//! # Example
//! ```no_run
//! # mod iced { pub mod widget { pub use iced_widget::*; } pub use iced_widget::Renderer; pub use iced_widget::core::*; }
//! # pub type Element<'a, Message> = iced_widget::core::Element<'a, Message, iced_widget::Theme, iced_widget::Renderer>;
//! #
//! use iced::widget::pick_list;
//!
//! struct State {
//!    favorite: Option<Fruit>,
//! }
//!
//! #[derive(Debug, Clone, Copy, PartialEq, Eq)]
//! enum Fruit {
//!     Apple,
//!     Orange,
//!     Strawberry,
//!     Tomato,
//! }
//!
//! #[derive(Debug, Clone)]
//! enum Message {
//!     FruitSelected(Fruit),
//! }
//!
//! fn view(state: &State) -> Element<'_, Message> {
//!     let fruits = [
//!         Fruit::Apple,
//!         Fruit::Orange,
//!         Fruit::Strawberry,
//!         Fruit::Tomato,
//!     ];
//!
//!     pick_list(
//!         fruits,
//!         state.favorite,
//!         Message::FruitSelected,
//!     )
//!     .placeholder("Select your favorite fruit...")
//!     .into()
//! }
//!
//! fn update(state: &mut State, message: Message) {
//!     match message {
//!         Message::FruitSelected(fruit) => {
//!             state.favorite = Some(fruit);
//!         }
//!     }
//! }
//!
//! impl std::fmt::Display for Fruit {
//!     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
//!         f.write_str(match self {
//!             Self::Apple => "Apple",
//!             Self::Orange => "Orange",
//!             Self::Strawberry => "Strawberry",
//!             Self::Tomato => "Tomato",
//!         })
//!     }
//! }
//! ```
use crate::core::alignment;
use crate::core::keyboard;
use crate::core::layout;
use crate::core::mouse;
use crate::core::overlay;
use crate::core::renderer;
use crate::core::text::paragraph;
use crate::core::text::{self, Text};
use crate::core::touch;
use crate::core::widget::tree::{self, Tree};
use crate::core::window;
use crate::core::{
    Background, Border, Clipboard, Color, Element, Event, Layout, Length,
    Padding, Pixels, Point, Rectangle, Shell, Size, Theme, Vector, Widget,
};
use crate::overlay::menu::{self, Menu};

use std::borrow::Borrow;
use std::f32;

/// A widget for selecting a single value from a list of options.
///
/// # Example
/// ```no_run
/// # mod iced { pub mod widget { pub use iced_widget::*; } pub use iced_widget::Renderer; pub use iced_widget::core::*; }
/// # pub type Element<'a, Message> = iced_widget::core::Element<'a, Message, iced_widget::Theme, iced_widget::Renderer>;
/// #
/// use iced::widget::pick_list;
///
/// struct State {
///    favorite: Option<Fruit>,
/// }
///
/// #[derive(Debug, Clone, Copy, PartialEq, Eq)]
/// enum Fruit {
///     Apple,
///     Orange,
///     Strawberry,
///     Tomato,
/// }
///
/// #[derive(Debug, Clone)]
/// enum Message {
///     FruitSelected(Fruit),
/// }
///
/// fn view(state: &State) -> Element<'_, Message> {
///     let fruits = [
///         Fruit::Apple,
///         Fruit::Orange,
///         Fruit::Strawberry,
///         Fruit::Tomato,
///     ];
///
///     pick_list(
///         fruits,
///         state.favorite,
///         Message::FruitSelected,
///     )
///     .placeholder("Select your favorite fruit...")
///     .into()
/// }
///
/// fn update(state: &mut State, message: Message) {
///     match message {
///         Message::FruitSelected(fruit) => {
///             state.favorite = Some(fruit);
///         }
///     }
/// }
///
/// impl std::fmt::Display for Fruit {
///     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
///         f.write_str(match self {
///             Self::Apple => "Apple",
///             Self::Orange => "Orange",
///             Self::Strawberry => "Strawberry",
///             Self::Tomato => "Tomato",
///         })
///     }
/// }
/// ```
#[allow(missing_debug_implementations)]
pub struct PickList<
    'a,
    T,
    L,
    V,
    Message,
    Theme = crate::Theme,
    Renderer = crate::Renderer,
> where
    T: ToString + PartialEq + Clone,
    L: Borrow<[T]> + 'a,
    V: Borrow<T> + 'a,
    Theme: Catalog,
    Renderer: text::Renderer,
{
    on_select: Box<dyn Fn(T) -> Message + 'a>,
    on_open: Option<Message>,
    on_close: Option<Message>,
    options: L,
    placeholder: Option<String>,
    selected: Option<V>,
    width: Length,
    padding: Padding,
    text_size: Option<Pixels>,
    text_line_height: text::LineHeight,
    text_shaping: text::Shaping,
    font: Option<Renderer::Font>,
    handle: Handle<Renderer::Font>,
    class: <Theme as Catalog>::Class<'a>,
    menu_class: <Theme as menu::Catalog>::Class<'a>,
    last_status: Option<Status>,
}

impl<'a, T, L, V, Message, Theme, Renderer>
    PickList<'a, T, L, V, Message, Theme, Renderer>
where
    T: ToString + PartialEq + Clone,
    L: Borrow<[T]> + 'a,
    V: Borrow<T> + 'a,
    Message: Clone,
    Theme: Catalog,
    Renderer: text::Renderer,
{
    /// Creates a new [`PickList`] with the given list of options, the current
    /// selected value, and the message to produce when an option is selected.
    pub fn new(
        options: L,
        selected: Option<V>,
        on_select: impl Fn(T) -> Message + 'a,
    ) -> Self {
        Self {
            on_select: Box::new(on_select),
            on_open: None,
            on_close: None,
            options,
            placeholder: None,
            selected,
            width: Length::Shrink,
            padding: crate::button::DEFAULT_PADDING,
            text_size: None,
            text_line_height: text::LineHeight::default(),
            text_shaping: text::Shaping::default(),
            font: None,
            handle: Handle::default(),
            class: <Theme as Catalog>::default(),
            menu_class: <Theme as Catalog>::default_menu(),
            last_status: None,
        }
    }

    /// Sets the placeholder of the [`PickList`].
    pub fn placeholder(mut self, placeholder: impl Into<String>) -> Self {
        self.placeholder = Some(placeholder.into());
        self
    }

    /// Sets the width of the [`PickList`].
    pub fn width(mut self, width: impl Into<Length>) -> Self {
        self.width = width.into();
        self
    }

    /// Sets the [`Padding`] of the [`PickList`].
    pub fn padding<P: Into<Padding>>(mut self, padding: P) -> Self {
        self.padding = padding.into();
        self
    }

    /// Sets the text size of the [`PickList`].
    pub fn text_size(mut self, size: impl Into<Pixels>) -> Self {
        self.text_size = Some(size.into());
        self
    }

    /// Sets the text [`text::LineHeight`] of the [`PickList`].
    pub fn text_line_height(
        mut self,
        line_height: impl Into<text::LineHeight>,
    ) -> Self {
        self.text_line_height = line_height.into();
        self
    }

    /// Sets the [`text::Shaping`] strategy of the [`PickList`].
    pub fn text_shaping(mut self, shaping: text::Shaping) -> Self {
        self.text_shaping = shaping;
        self
    }

    /// Sets the font of the [`PickList`].
    pub fn font(mut self, font: impl Into<Renderer::Font>) -> Self {
        self.font = Some(font.into());
        self
    }

    /// Sets the [`Handle`] of the [`PickList`].
    pub fn handle(mut self, handle: Handle<Renderer::Font>) -> Self {
        self.handle = handle;
        self
    }

    /// Sets the message that will be produced when the [`PickList`] is opened.
    pub fn on_open(mut self, on_open: Message) -> Self {
        self.on_open = Some(on_open);
        self
    }

    /// Sets the message that will be produced when the [`PickList`] is closed.
    pub fn on_close(mut self, on_close: Message) -> Self {
        self.on_close = Some(on_close);
        self
    }

    /// Sets the style of the [`PickList`].
    #[must_use]
    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
    where
        <Theme as Catalog>::Class<'a>: From<StyleFn<'a, Theme>>,
    {
        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
        self
    }

    /// Sets the style of the [`Menu`].
    #[must_use]
    pub fn menu_style(
        mut self,
        style: impl Fn(&Theme) -> menu::Style + 'a,
    ) -> Self
    where
        <Theme as menu::Catalog>::Class<'a>: From<menu::StyleFn<'a, Theme>>,
    {
        self.menu_class = (Box::new(style) as menu::StyleFn<'a, Theme>).into();
        self
    }

    /// Sets the style class of the [`PickList`].
    #[cfg(feature = "advanced")]
    #[must_use]
    pub fn class(
        mut self,
        class: impl Into<<Theme as Catalog>::Class<'a>>,
    ) -> Self {
        self.class = class.into();
        self
    }

    /// Sets the style class of the [`Menu`].
    #[cfg(feature = "advanced")]
    #[must_use]
    pub fn menu_class(
        mut self,
        class: impl Into<<Theme as menu::Catalog>::Class<'a>>,
    ) -> Self {
        self.menu_class = class.into();
        self
    }
}

impl<'a, T, L, V, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
    for PickList<'a, T, L, V, Message, Theme, Renderer>
where
    T: Clone + ToString + PartialEq + 'a,
    L: Borrow<[T]>,
    V: Borrow<T>,
    Message: Clone + 'a,
    Theme: Catalog + 'a,
    Renderer: text::Renderer + 'a,
{
    fn tag(&self) -> tree::Tag {
        tree::Tag::of::<State<Renderer::Paragraph>>()
    }

    fn state(&self) -> tree::State {
        tree::State::new(State::<Renderer::Paragraph>::new())
    }

    fn size(&self) -> Size<Length> {
        Size {
            width: self.width,
            height: Length::Shrink,
        }
    }

    fn layout(
        &self,
        tree: &mut Tree,
        renderer: &Renderer,
        limits: &layout::Limits,
    ) -> layout::Node {
        let state = tree.state.downcast_mut::<State<Renderer::Paragraph>>();

        let font = self.font.unwrap_or_else(|| renderer.default_font());
        let text_size =
            self.text_size.unwrap_or_else(|| renderer.default_size());
        let options = self.options.borrow();

        state.options.resize_with(options.len(), Default::default);

        let option_text = Text {
            content: "",
            bounds: Size::new(
                f32::INFINITY,
                self.text_line_height.to_absolute(text_size).into(),
            ),
            size: text_size,
            line_height: self.text_line_height,
            font,
            horizontal_alignment: alignment::Horizontal::Left,
            vertical_alignment: alignment::Vertical::Center,
            shaping: self.text_shaping,
            wrapping: text::Wrapping::default(),
        };

        for (option, paragraph) in options.iter().zip(state.options.iter_mut())
        {
            let label = option.to_string();

            paragraph.update(Text {
                content: &label,
                ..option_text
            });
        }

        if let Some(placeholder) = &self.placeholder {
            state.placeholder.update(Text {
                content: placeholder,
                ..option_text
            });
        }

        let max_width = match self.width {
            Length::Shrink => {
                let labels_width =
                    state.options.iter().fold(0.0, |width, paragraph| {
                        f32::max(width, paragraph.min_width())
                    });

                labels_width.max(
                    self.placeholder
                        .as_ref()
                        .map(|_| state.placeholder.min_width())
                        .unwrap_or(0.0),
                )
            }
            _ => 0.0,
        };

        let size = {
            let intrinsic = Size::new(
                max_width + text_size.0 + self.padding.left,
                f32::from(self.text_line_height.to_absolute(text_size)),
            );

            limits
                .width(self.width)
                .shrink(self.padding)
                .resolve(self.width, Length::Shrink, intrinsic)
                .expand(self.padding)
        };

        layout::Node::new(size)
    }

    fn update(
        &mut self,
        tree: &mut Tree,
        event: Event,
        layout: Layout<'_>,
        cursor: mouse::Cursor,
        _renderer: &Renderer,
        _clipboard: &mut dyn Clipboard,
        shell: &mut Shell<'_, Message>,
        _viewport: &Rectangle,
    ) {
        let state = tree.state.downcast_mut::<State<Renderer::Paragraph>>();

        match event {
            Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left))
            | Event::Touch(touch::Event::FingerPressed { .. }) => {
                if state.is_open {
                    // Event wasn't processed by overlay, so cursor was clicked either outside its
                    // bounds or on the drop-down, either way we close the overlay.
                    state.is_open = false;

                    if let Some(on_close) = &self.on_close {
                        shell.publish(on_close.clone());
                    }

                    shell.capture_event();
                } else if cursor.is_over(layout.bounds()) {
                    let selected = self.selected.as_ref().map(Borrow::borrow);

                    state.is_open = true;
                    state.hovered_option = self
                        .options
                        .borrow()
                        .iter()
                        .position(|option| Some(option) == selected);

                    if let Some(on_open) = &self.on_open {
                        shell.publish(on_open.clone());
                    }

                    shell.capture_event();
                }
            }
            Event::Mouse(mouse::Event::WheelScrolled {
                delta: mouse::ScrollDelta::Lines { y, .. },
            }) => {
                if state.keyboard_modifiers.command()
                    && cursor.is_over(layout.bounds())
                    && !state.is_open
                {
                    fn find_next<'a, T: PartialEq>(
                        selected: &'a T,
                        mut options: impl Iterator<Item = &'a T>,
                    ) -> Option<&'a T> {
                        let _ = options.find(|&option| option == selected);

                        options.next()
                    }

                    let options = self.options.borrow();
                    let selected = self.selected.as_ref().map(Borrow::borrow);

                    let next_option = if y < 0.0 {
                        if let Some(selected) = selected {
                            find_next(selected, options.iter())
                        } else {
                            options.first()
                        }
                    } else if y > 0.0 {
                        if let Some(selected) = selected {
                            find_next(selected, options.iter().rev())
                        } else {
                            options.last()
                        }
                    } else {
                        None
                    };

                    if let Some(next_option) = next_option {
                        shell.publish((self.on_select)(next_option.clone()));
                    }

                    shell.capture_event();
                }
            }
            Event::Keyboard(keyboard::Event::ModifiersChanged(modifiers)) => {
                state.keyboard_modifiers = modifiers;
            }
            _ => {}
        };

        let status = {
            let is_hovered = cursor.is_over(layout.bounds());

            if state.is_open {
                Status::Opened { is_hovered }
            } else if is_hovered {
                Status::Hovered
            } else {
                Status::Active
            }
        };

        if let Event::Window(window::Event::RedrawRequested(_now)) = event {
            self.last_status = Some(status);
        } else if self
            .last_status
            .is_some_and(|last_status| last_status != status)
        {
            shell.request_redraw();
        }
    }

    fn mouse_interaction(
        &self,
        _tree: &Tree,
        layout: Layout<'_>,
        cursor: mouse::Cursor,
        _viewport: &Rectangle,
        _renderer: &Renderer,
    ) -> mouse::Interaction {
        let bounds = layout.bounds();
        let is_mouse_over = cursor.is_over(bounds);

        if is_mouse_over {
            mouse::Interaction::Pointer
        } else {
            mouse::Interaction::default()
        }
    }

    fn draw(
        &self,
        tree: &Tree,
        renderer: &mut Renderer,
        theme: &Theme,
        _style: &renderer::Style,
        layout: Layout<'_>,
        _cursor: mouse::Cursor,
        viewport: &Rectangle,
    ) {
        let font = self.font.unwrap_or_else(|| renderer.default_font());
        let selected = self.selected.as_ref().map(Borrow::borrow);
        let state = tree.state.downcast_ref::<State<Renderer::Paragraph>>();

        let bounds = layout.bounds();

        let style = Catalog::style(
            theme,
            &self.class,
            self.last_status.unwrap_or(Status::Active),
        );

        renderer.fill_quad(
            renderer::Quad {
                bounds,
                border: style.border,
                ..renderer::Quad::default()
            },
            style.background,
        );

        let handle = match &self.handle {
            Handle::Arrow { size } => Some((
                Renderer::ICON_FONT,
                Renderer::ARROW_DOWN_ICON,
                *size,
                text::LineHeight::default(),
                text::Shaping::Basic,
            )),
            Handle::Static(Icon {
                font,
                code_point,
                size,
                line_height,
                shaping,
            }) => Some((*font, *code_point, *size, *line_height, *shaping)),
            Handle::Dynamic { open, closed } => {
                if state.is_open {
                    Some((
                        open.font,
                        open.code_point,
                        open.size,
                        open.line_height,
                        open.shaping,
                    ))
                } else {
                    Some((
                        closed.font,
                        closed.code_point,
                        closed.size,
                        closed.line_height,
                        closed.shaping,
                    ))
                }
            }
            Handle::None => None,
        };

        if let Some((font, code_point, size, line_height, shaping)) = handle {
            let size = size.unwrap_or_else(|| renderer.default_size());

            renderer.fill_text(
                Text {
                    content: code_point.to_string(),
                    size,
                    line_height,
                    font,
                    bounds: Size::new(
                        bounds.width,
                        f32::from(line_height.to_absolute(size)),
                    ),
                    horizontal_alignment: alignment::Horizontal::Right,
                    vertical_alignment: alignment::Vertical::Center,
                    shaping,
                    wrapping: text::Wrapping::default(),
                },
                Point::new(
                    bounds.x + bounds.width - self.padding.right,
                    bounds.center_y(),
                ),
                style.handle_color,
                *viewport,
            );
        }

        let label = selected.map(ToString::to_string);

        if let Some(label) = label.or_else(|| self.placeholder.clone()) {
            let text_size =
                self.text_size.unwrap_or_else(|| renderer.default_size());

            renderer.fill_text(
                Text {
                    content: label,
                    size: text_size,
                    line_height: self.text_line_height,
                    font,
                    bounds: Size::new(
                        bounds.width - self.padding.horizontal(),
                        f32::from(self.text_line_height.to_absolute(text_size)),
                    ),
                    horizontal_alignment: alignment::Horizontal::Left,
                    vertical_alignment: alignment::Vertical::Center,
                    shaping: self.text_shaping,
                    wrapping: text::Wrapping::default(),
                },
                Point::new(bounds.x + self.padding.left, bounds.center_y()),
                if selected.is_some() {
                    style.text_color
                } else {
                    style.placeholder_color
                },
                *viewport,
            );
        }
    }

    fn overlay<'b>(
        &'b mut self,
        tree: &'b mut Tree,
        layout: Layout<'_>,
        renderer: &Renderer,
        translation: Vector,
    ) -> Option<overlay::Element<'b, Message, Theme, Renderer>> {
        let state = tree.state.downcast_mut::<State<Renderer::Paragraph>>();
        let font = self.font.unwrap_or_else(|| renderer.default_font());

        if state.is_open {
            let bounds = layout.bounds();

            let on_select = &self.on_select;

            let mut menu = Menu::new(
                &mut state.menu,
                self.options.borrow(),
                &mut state.hovered_option,
                |option| {
                    state.is_open = false;

                    (on_select)(option)
                },
                None,
                &self.menu_class,
            )
            .width(bounds.width)
            .padding(self.padding)
            .font(font)
            .text_shaping(self.text_shaping);

            if let Some(text_size) = self.text_size {
                menu = menu.text_size(text_size);
            }

            Some(menu.overlay(layout.position() + translation, bounds.height))
        } else {
            None
        }
    }
}

impl<'a, T, L, V, Message, Theme, Renderer>
    From<PickList<'a, T, L, V, Message, Theme, Renderer>>
    for Element<'a, Message, Theme, Renderer>
where
    T: Clone + ToString + PartialEq + 'a,
    L: Borrow<[T]> + 'a,
    V: Borrow<T> + 'a,
    Message: Clone + 'a,
    Theme: Catalog + 'a,
    Renderer: text::Renderer + 'a,
{
    fn from(
        pick_list: PickList<'a, T, L, V, Message, Theme, Renderer>,
    ) -> Self {
        Self::new(pick_list)
    }
}

#[derive(Debug)]
struct State<P: text::Paragraph> {
    menu: menu::State,
    keyboard_modifiers: keyboard::Modifiers,
    is_open: bool,
    hovered_option: Option<usize>,
    options: Vec<paragraph::Plain<P>>,
    placeholder: paragraph::Plain<P>,
}

impl<P: text::Paragraph> State<P> {
    /// Creates a new [`State`] for a [`PickList`].
    fn new() -> Self {
        Self {
            menu: menu::State::default(),
            keyboard_modifiers: keyboard::Modifiers::default(),
            is_open: bool::default(),
            hovered_option: Option::default(),
            options: Vec::new(),
            placeholder: paragraph::Plain::default(),
        }
    }
}

impl<P: text::Paragraph> Default for State<P> {
    fn default() -> Self {
        Self::new()
    }
}

/// The handle to the right side of the [`PickList`].
#[derive(Debug, Clone, PartialEq)]
pub enum Handle<Font> {
    /// Displays an arrow icon (▼).
    ///
    /// This is the default.
    Arrow {
        /// Font size of the content.
        size: Option<Pixels>,
    },
    /// A custom static handle.
    Static(Icon<Font>),
    /// A custom dynamic handle.
    Dynamic {
        /// The [`Icon`] used when [`PickList`] is closed.
        closed: Icon<Font>,
        /// The [`Icon`] used when [`PickList`] is open.
        open: Icon<Font>,
    },
    /// No handle will be shown.
    None,
}

impl<Font> Default for Handle<Font> {
    fn default() -> Self {
        Self::Arrow { size: None }
    }
}

/// The icon of a [`Handle`].
#[derive(Debug, Clone, PartialEq)]
pub struct Icon<Font> {
    /// Font that will be used to display the `code_point`,
    pub font: Font,
    /// The unicode code point that will be used as the icon.
    pub code_point: char,
    /// Font size of the content.
    pub size: Option<Pixels>,
    /// Line height of the content.
    pub line_height: text::LineHeight,
    /// The shaping strategy of the icon.
    pub shaping: text::Shaping,
}

/// The possible status of a [`PickList`].
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum Status {
    /// The [`PickList`] can be interacted with.
    Active,
    /// The [`PickList`] is being hovered.
    Hovered,
    /// The [`PickList`] is open.
    Opened {
        /// Whether the [`PickList`] is hovered, while open.
        is_hovered: bool,
    },
}

/// The appearance of a pick list.
#[derive(Debug, Clone, Copy, PartialEq)]
pub struct Style {
    /// The text [`Color`] of the pick list.
    pub text_color: Color,
    /// The placeholder [`Color`] of the pick list.
    pub placeholder_color: Color,
    /// The handle [`Color`] of the pick list.
    pub handle_color: Color,
    /// The [`Background`] of the pick list.
    pub background: Background,
    /// The [`Border`] of the pick list.
    pub border: Border,
}

/// The theme catalog of a [`PickList`].
pub trait Catalog: menu::Catalog {
    /// The item class of the [`Catalog`].
    type Class<'a>;

    /// The default class produced by the [`Catalog`].
    fn default<'a>() -> <Self as Catalog>::Class<'a>;

    /// The default class for the menu of the [`PickList`].
    fn default_menu<'a>() -> <Self as menu::Catalog>::Class<'a> {
        <Self as menu::Catalog>::default()
    }

    /// The [`Style`] of a class with the given status.
    fn style(
        &self,
        class: &<Self as Catalog>::Class<'_>,
        status: Status,
    ) -> Style;
}

/// A styling function for a [`PickList`].
///
/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;

impl Catalog for Theme {
    type Class<'a> = StyleFn<'a, Self>;

    fn default<'a>() -> StyleFn<'a, Self> {
        Box::new(default)
    }

    fn style(&self, class: &StyleFn<'_, Self>, status: Status) -> Style {
        class(self, status)
    }
}

/// The default style of the field of a [`PickList`].
pub fn default(theme: &Theme, status: Status) -> Style {
    let palette = theme.extended_palette();

    let active = Style {
        text_color: palette.background.weak.text,
        background: palette.background.weak.color.into(),
        placeholder_color: palette.background.strong.color,
        handle_color: palette.background.weak.text,
        border: Border {
            radius: 2.0.into(),
            width: 1.0,
            color: palette.background.strong.color,
        },
    };

    match status {
        Status::Active => active,
        Status::Hovered | Status::Opened { .. } => Style {
            border: Border {
                color: palette.primary.strong.color,
                ..active.border
            },
            ..active
        },
    }
}