vizia_core/views/
rating.rs

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1use crate::{icons::ICON_STAR_FILLED, prelude::*};
2
3/// A view which represents a rating as a number of filled stars.
4#[derive(Lens)]
5pub struct Rating {
6    rating: u32,
7    max_rating: u32,
8    on_change: Option<Box<dyn Fn(&mut EventContext, u32)>>,
9}
10
11pub(crate) enum RatingEvent {
12    SetRating(u32),
13    EmitRating,
14    Increment,
15    Decrement,
16}
17
18impl Rating {
19    /// Creates a new [Rating] view.
20    pub fn new(cx: &mut Context, max_rating: u32, lens: impl Lens<Target = u32>) -> Handle<Self> {
21        Self { rating: lens.get(cx), max_rating, on_change: None }
22            .build(cx, |cx| {
23                for i in 1..max_rating + 1 {
24                    Svg::new(cx, ICON_STAR_FILLED)
25                        // .navigable(true)
26                        .checkable(true)
27                        .numeric_value(1)
28                        .role(Role::RadioButton)
29                        .checked(lens.map(move |val| *val >= i))
30                        .toggle_class("foo", Rating::rating.map(move |val| *val >= i))
31                        .on_hover(move |ex| ex.emit(RatingEvent::SetRating(i)))
32                        .on_press(|ex| ex.emit(RatingEvent::EmitRating));
33                }
34            })
35            .numeric_value(Self::rating)
36            .navigable(true)
37            .role(Role::RadioGroup)
38            .bind(lens, |handle, lens| {
39                let val = lens.get(&handle);
40                handle.modify(|rating| rating.rating = val);
41            })
42    }
43}
44
45impl View for Rating {
46    fn element(&self) -> Option<&'static str> {
47        Some("rating")
48    }
49
50    fn event(&mut self, cx: &mut EventContext, event: &mut Event) {
51        event.map(|rating_event, _| match rating_event {
52            RatingEvent::SetRating(val) => self.rating = *val,
53            RatingEvent::EmitRating => {
54                if let Some(callback) = &self.on_change {
55                    (callback)(cx, self.rating)
56                }
57            }
58            RatingEvent::Increment => {
59                self.rating += 1;
60                self.rating %= self.max_rating + 1;
61                cx.emit(RatingEvent::EmitRating);
62            }
63            RatingEvent::Decrement => {
64                self.rating =
65                    if self.rating == 0 { self.max_rating } else { self.rating.saturating_sub(1) };
66                cx.emit(RatingEvent::EmitRating);
67            }
68        });
69
70        event.map(|window_event, _| match window_event {
71            WindowEvent::KeyDown(code, _) => match code {
72                Code::ArrowLeft => {
73                    cx.emit(RatingEvent::Decrement);
74                }
75
76                Code::ArrowRight => {
77                    cx.emit(RatingEvent::Increment);
78                }
79
80                _ => {}
81            },
82
83            _ => {}
84        });
85    }
86}
87
88impl Handle<'_, Rating> {
89    /// Set the callback which is triggered when the rating changes.
90    pub fn on_change<F>(self, callback: F) -> Self
91    where
92        F: 'static + Fn(&mut EventContext, u32),
93    {
94        self.modify(|rating| rating.on_change = Some(Box::new(callback)))
95    }
96}
vizia_core/views/rating.rs

vizia_core/views/
rating.rs
