//! Show toggle controls using togglers.
use std::hash::Hash;
use crate::{
event, layout, mouse, row, text, Align, Clipboard, Element, Event, Hasher,
HorizontalAlignment, Layout, Length, Point, Rectangle, Row, Text,
VerticalAlignment, Widget,
};
/// A toggler widget
///
/// # Example
///
/// ```
/// # type Toggler<Message> = iced_native::Toggler<Message, iced_native::renderer::Null>;
/// #
/// pub enum Message {
/// TogglerToggled(bool),
/// }
///
/// let is_active = true;
///
/// Toggler::new(is_active, String::from("Toggle me!"), |b| Message::TogglerToggled(b));
/// ```
#[allow(missing_debug_implementations)]
pub struct Toggler<Message, Renderer: self::Renderer + text::Renderer> {
is_active: bool,
on_toggle: Box<dyn Fn(bool) -> Message>,
label: Option<String>,
width: Length,
size: u16,
text_size: Option<u16>,
text_alignment: HorizontalAlignment,
spacing: u16,
font: Renderer::Font,
style: Renderer::Style,
}
impl<Message, Renderer: self::Renderer + text::Renderer>
Toggler<Message, Renderer>
{
/// Creates a new [`Toggler`].
///
/// It expects:
/// * a boolean describing whether the [`Toggler`] is checked or not
/// * An optional label for the [`Toggler`]
/// * a function that will be called when the [`Toggler`] is toggled. It
/// will receive the new state of the [`Toggler`] and must produce a
/// `Message`.
pub fn new<F>(
is_active: bool,
label: impl Into<Option<String>>,
f: F,
) -> Self
where
F: 'static + Fn(bool) -> Message,
{
Toggler {
is_active,
on_toggle: Box::new(f),
label: label.into(),
width: Length::Fill,
size: <Renderer as self::Renderer>::DEFAULT_SIZE,
text_size: None,
text_alignment: HorizontalAlignment::Left,
spacing: 0,
font: Renderer::Font::default(),
style: Renderer::Style::default(),
}
}
/// Sets the size of the [`Toggler`].
pub fn size(mut self, size: u16) -> Self {
self.size = size;
self
}
/// Sets the width of the [`Toggler`].
pub fn width(mut self, width: Length) -> Self {
self.width = width;
self
}
/// Sets the text size o the [`Toggler`].
pub fn text_size(mut self, text_size: u16) -> Self {
self.text_size = Some(text_size);
self
}
/// Sets the horizontal alignment of the text of the [`Toggler`]
pub fn text_alignment(mut self, alignment: HorizontalAlignment) -> Self {
self.text_alignment = alignment;
self
}
/// Sets the spacing between the [`Toggler`] and the text.
pub fn spacing(mut self, spacing: u16) -> Self {
self.spacing = spacing;
self
}
/// Sets the [`Font`] of the text of the [`Toggler`]
pub fn font(mut self, font: Renderer::Font) -> Self {
self.font = font;
self
}
/// Sets the style of the [`Toggler`].
pub fn style(mut self, style: impl Into<Renderer::Style>) -> Self {
self.style = style.into();
self
}
}
impl<Message, Renderer> Widget<Message, Renderer> for Toggler<Message, Renderer>
where
Renderer: self::Renderer + text::Renderer + row::Renderer,
{
fn width(&self) -> Length {
self.width
}
fn height(&self) -> Length {
Length::Shrink
}
fn layout(
&self,
renderer: &Renderer,
limits: &layout::Limits,
) -> layout::Node {
let mut row = Row::<(), Renderer>::new()
.width(self.width)
.spacing(self.spacing)
.align_items(Align::Center);
if let Some(label) = &self.label {
row = row.push(
Text::new(label)
.horizontal_alignment(self.text_alignment)
.font(self.font)
.width(self.width)
.size(self.text_size.unwrap_or(renderer.default_size())),
);
}
row = row.push(
Row::new()
.width(Length::Units(2 * self.size))
.height(Length::Units(self.size)),
);
row.layout(renderer, limits)
}
fn on_event(
&mut self,
event: Event,
layout: Layout<'_>,
cursor_position: Point,
_renderer: &Renderer,
_clipboard: &mut dyn Clipboard,
messages: &mut Vec<Message>,
) -> event::Status {
match event {
Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left)) => {
let mouse_over = layout.bounds().contains(cursor_position);
if mouse_over {
messages.push((self.on_toggle)(!self.is_active));
event::Status::Captured
} else {
event::Status::Ignored
}
}
_ => event::Status::Ignored,
}
}
fn draw(
&self,
renderer: &mut Renderer,
defaults: &Renderer::Defaults,
layout: Layout<'_>,
cursor_position: Point,
_viewport: &Rectangle,
) -> Renderer::Output {
let bounds = layout.bounds();
let mut children = layout.children();
let label = match &self.label {
Some(label) => {
let label_layout = children.next().unwrap();
Some(text::Renderer::draw(
renderer,
defaults,
label_layout.bounds(),
&label,
self.text_size.unwrap_or(renderer.default_size()),
self.font,
None,
self.text_alignment,
VerticalAlignment::Center,
))
}
None => None,
};
let toggler_layout = children.next().unwrap();
let toggler_bounds = toggler_layout.bounds();
let is_mouse_over = bounds.contains(cursor_position);
self::Renderer::draw(
renderer,
toggler_bounds,
self.is_active,
is_mouse_over,
label,
&self.style,
)
}
fn hash_layout(&self, state: &mut Hasher) {
struct Marker;
std::any::TypeId::of::<Marker>().hash(state);
self.label.hash(state)
}
}
/// The renderer of a [`Toggler`].
///
/// Your [renderer] will need to implement this trait before being
/// able to use a [`Toggler`] in your user interface.
///
/// [renderer]: ../../renderer/index.html
pub trait Renderer: crate::Renderer {
/// The style supported by this renderer.
type Style: Default;
/// The default size of a [`Toggler`].
const DEFAULT_SIZE: u16;
/// Draws a [`Toggler`].
///
/// It receives:
/// * the bounds of the [`Toggler`]
/// * whether the [`Toggler`] is activated or not
/// * whether the mouse is over the [`Toggler`] or not
/// * the drawn label of the [`Toggler`]
/// * the style of the [`Toggler`]
fn draw(
&mut self,
bounds: Rectangle,
is_active: bool,
is_mouse_over: bool,
label: Option<Self::Output>,
style: &Self::Style,
) -> Self::Output;
}
impl<'a, Message, Renderer> From<Toggler<Message, Renderer>>
for Element<'a, Message, Renderer>
where
Renderer: 'a + self::Renderer + text::Renderer + row::Renderer,
Message: 'a,
{
fn from(
toggler: Toggler<Message, Renderer>,
) -> Element<'a, Message, Renderer> {
Element::new(toggler)
}
}
