Merge pull request #575 from clarkmoody/scrollable-width

Custom Scrollbar Width

6 files changed, 399 insertions, 0 deletions

diff --git a/examples/README.md b/examples/README.md
index 34a916a1..32ccf724 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -103,6 +103,7 @@ A bunch of simpler examples exist:
 - [`pick_list`](pick_list), a dropdown list of selectable options.
 - [`pokedex`](pokedex), an application that displays a random Pokédex entry (sprite included!) by using the [PokéAPI].
 - [`progress_bar`](progress_bar), a simple progress bar that can be filled by using a slider.
+- [`scrollable`](scrollable), a showcase of the various scrollbar width options.
 - [`solar_system`](solar_system), an animated solar system drawn using the `Canvas` widget and showcasing how to compose different transforms.
 - [`stopwatch`](stopwatch), a watch with start/stop and reset buttons showcasing how to listen to time.
 - [`svg`](svg), an application that renders the [Ghostscript Tiger] by leveraging the `Svg` widget.
diff --git a/examples/scrollable/Cargo.toml b/examples/scrollable/Cargo.toml
new file mode 100644
index 00000000..12753fb6
--- /dev/null
+++ b/examples/scrollable/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "scrollable"
+version = "0.1.0"
+authors = ["Clark Moody <clark@clarkmoody.com>"]
+edition = "2018"
+publish = false
+
+[dependencies]
+iced = { path = "../.." }
diff --git a/examples/scrollable/README.md b/examples/scrollable/README.md
new file mode 100644
index 00000000..ed0e31b5
--- /dev/null
+++ b/examples/scrollable/README.md
@@ -0,0 +1,15 @@
+# Scrollable
+An example showcasing the various size and style options for the Scrollable.
+
+All the example code is located in the __[`main`](src/main.rs)__ file.
+
+<div align="center">
+  <a href="./screenshot.png">
+    <img src="./screenshot.png" height="640px">
+  </a>
+</div>
+
+You can run it with `cargo run`:
+```
+cargo run --package scrollable
+```
diff --git a/examples/scrollable/screenshot.png b/examples/scrollable/screenshot.png
new file mode 100644
index 00000000..2d800251
--- /dev/null
+++ b/examples/scrollable/screenshot.png
diff --git a/examples/scrollable/src/main.rs b/examples/scrollable/src/main.rs
new file mode 100644
index 00000000..8dd2e20c
--- /dev/null
+++ b/examples/scrollable/src/main.rs
@@ -0,0 +1,184 @@
+mod style;
+
+use iced::{
+    scrollable, Column, Container, Element, Length, Radio, Row, Rule, Sandbox,
+    Scrollable, Settings, Space, Text,
+};
+
+pub fn main() -> iced::Result {
+    ScrollableDemo::run(Settings::default())
+}
+
+struct ScrollableDemo {
+    theme: style::Theme,
+    variants: Vec<Variant>,
+}
+
+#[derive(Debug, Clone)]
+enum Message {
+    ThemeChanged(style::Theme),
+}
+
+impl Sandbox for ScrollableDemo {
+    type Message = Message;
+
+    fn new() -> Self {
+        ScrollableDemo {
+            theme: Default::default(),
+            variants: Variant::all(),
+        }
+    }
+
+    fn title(&self) -> String {
+        String::from("Scrollable - Iced")
+    }
+
+    fn update(&mut self, message: Message) {
+        match message {
+            Message::ThemeChanged(theme) => self.theme = theme,
+        }
+    }
+
+    fn view(&mut self) -> Element<Message> {
+        let ScrollableDemo {
+            theme, variants, ..
+        } = self;
+
+        let choose_theme = style::Theme::ALL.iter().fold(
+            Column::new().spacing(10).push(Text::new("Choose a theme:")),
+            |column, option| {
+                column.push(
+                    Radio::new(
+                        *option,
+                        &format!("{:?}", option),
+                        Some(*theme),
+                        Message::ThemeChanged,
+                    )
+                    .style(*theme),
+                )
+            },
+        );
+
+        let scrollable_row = Row::with_children(
+            variants
+                .iter_mut()
+                .map(|variant| {
+                    let mut scrollable = Scrollable::new(&mut variant.state)
+                        .padding(10)
+                        .width(Length::Fill)
+                        .height(Length::Fill)
+                        .style(*theme)
+                        .push(Text::new(variant.title));
+
+                    if let Some(scrollbar_width) = variant.scrollbar_width {
+                        scrollable = scrollable
+                            .scrollbar_width(scrollbar_width)
+                            .push(Text::new(format!(
+                                "scrollbar_width: {:?}",
+                                scrollbar_width
+                            )));
+                    }
+
+                    if let Some(scrollbar_margin) = variant.scrollbar_margin {
+                        scrollable = scrollable
+                            .scrollbar_margin(scrollbar_margin)
+                            .push(Text::new(format!(
+                                "scrollbar_margin: {:?}",
+                                scrollbar_margin
+                            )));
+                    }
+
+                    if let Some(scroller_width) = variant.scroller_width {
+                        scrollable = scrollable
+                            .scroller_width(scroller_width)
+                            .push(Text::new(format!(
+                                "scroller_width: {:?}",
+                                scroller_width
+                            )));
+                    }
+
+                    scrollable = scrollable
+                        .push(Space::with_height(Length::Units(100)))
+                        .push(Text::new(
+                            "Some content that should wrap within the \
+                            scrollable. Let's output a lot of short words, so \
+                            that we'll make sure to see how wrapping works \
+                            with these scrollbars.",
+                        ))
+                        .push(Space::with_height(Length::Units(1200)))
+                        .push(Text::new("Middle"))
+                        .push(Space::with_height(Length::Units(1200)))
+                        .push(Text::new("The End."));
+
+                    Container::new(scrollable)
+                        .width(Length::Fill)
+                        .height(Length::Fill)
+                        .style(*theme)
+                        .into()
+                })
+                .collect(),
+        )
+        .spacing(20)
+        .width(Length::Fill)
+        .height(Length::Fill);
+
+        let content = Column::new()
+            .spacing(20)
+            .padding(20)
+            .push(choose_theme)
+            .push(Rule::horizontal(20).style(self.theme))
+            .push(scrollable_row);
+
+        Container::new(content)
+            .width(Length::Fill)
+            .height(Length::Fill)
+            .center_x()
+            .center_y()
+            .style(self.theme)
+            .into()
+    }
+}
+
+/// A version of a scrollable
+struct Variant {
+    title: &'static str,
+    state: scrollable::State,
+    scrollbar_width: Option<u16>,
+    scrollbar_margin: Option<u16>,
+    scroller_width: Option<u16>,
+}
+
+impl Variant {
+    pub fn all() -> Vec<Self> {
+        vec![
+            Self {
+                title: "Default Scrollbar",
+                state: scrollable::State::new(),
+                scrollbar_width: None,
+                scrollbar_margin: None,
+                scroller_width: None,
+            },
+            Self {
+                title: "Slimmed & Margin",
+                state: scrollable::State::new(),
+                scrollbar_width: Some(4),
+                scrollbar_margin: Some(3),
+                scroller_width: Some(4),
+            },
+            Self {
+                title: "Wide Scroller",
+                state: scrollable::State::new(),
+                scrollbar_width: Some(4),
+                scrollbar_margin: None,
+                scroller_width: Some(10),
+            },
+            Self {
+                title: "Narrow Scroller",
+                state: scrollable::State::new(),
+                scrollbar_width: Some(10),
+                scrollbar_margin: None,
+                scroller_width: Some(4),
+            },
+        ]
+    }
+}
diff --git a/examples/scrollable/src/style.rs b/examples/scrollable/src/style.rs
new file mode 100644
index 00000000..24d711ac
--- /dev/null
+++ b/examples/scrollable/src/style.rs
@@ -0,0 +1,190 @@
+use iced::{container, radio, rule, scrollable};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Theme {
+    Light,
+    Dark,
+}
+
+impl Theme {
+    pub const ALL: [Theme; 2] = [Theme::Light, Theme::Dark];
+}
+
+impl Default for Theme {
+    fn default() -> Theme {
+        Theme::Light
+    }
+}
+
+impl From<Theme> for Box<dyn container::StyleSheet> {
+    fn from(theme: Theme) -> Self {
+        match theme {
+            Theme::Light => Default::default(),
+            Theme::Dark => dark::Container.into(),
+        }
+    }
+}
+
+impl From<Theme> for Box<dyn radio::StyleSheet> {
+    fn from(theme: Theme) -> Self {
+        match theme {
+            Theme::Light => Default::default(),
+            Theme::Dark => dark::Radio.into(),
+        }
+    }
+}
+
+impl From<Theme> for Box<dyn scrollable::StyleSheet> {
+    fn from(theme: Theme) -> Self {
+        match theme {
+            Theme::Light => Default::default(),
+            Theme::Dark => dark::Scrollable.into(),
+        }
+    }
+}
+
+impl From<Theme> for Box<dyn rule::StyleSheet> {
+    fn from(theme: Theme) -> Self {
+        match theme {
+            Theme::Light => Default::default(),
+            Theme::Dark => dark::Rule.into(),
+        }
+    }
+}
+
+mod dark {
+    use iced::{container, radio, rule, scrollable, Color};
+
+    const BACKGROUND: Color = Color::from_rgb(
+        0x36 as f32 / 255.0,
+        0x39 as f32 / 255.0,
+        0x3F as f32 / 255.0,
+    );
+
+    const SURFACE: Color = Color::from_rgb(
+        0x40 as f32 / 255.0,
+        0x44 as f32 / 255.0,
+        0x4B as f32 / 255.0,
+    );
+
+    const ACCENT: Color = Color::from_rgb(
+        0x6F as f32 / 255.0,
+        0xFF as f32 / 255.0,
+        0xE9 as f32 / 255.0,
+    );
+
+    const ACTIVE: Color = Color::from_rgb(
+        0x72 as f32 / 255.0,
+        0x89 as f32 / 255.0,
+        0xDA as f32 / 255.0,
+    );
+
+    const SCROLLBAR: Color = Color::from_rgb(
+        0x2E as f32 / 255.0,
+        0x33 as f32 / 255.0,
+        0x38 as f32 / 255.0,
+    );
+
+    const SCROLLER: Color = Color::from_rgb(
+        0x20 as f32 / 255.0,
+        0x22 as f32 / 255.0,
+        0x25 as f32 / 255.0,
+    );
+
+    pub struct Container;
+
+    impl container::StyleSheet for Container {
+        fn style(&self) -> container::Style {
+            container::Style {
+                background: Color {
+                    a: 0.99,
+                    ..BACKGROUND
+                }
+                .into(),
+                text_color: Color::WHITE.into(),
+                ..container::Style::default()
+            }
+        }
+    }
+
+    pub struct Radio;
+
+    impl radio::StyleSheet for Radio {
+        fn active(&self) -> radio::Style {
+            radio::Style {
+                background: SURFACE.into(),
+                dot_color: ACTIVE,
+                border_width: 1,
+                border_color: ACTIVE,
+            }
+        }
+
+        fn hovered(&self) -> radio::Style {
+            radio::Style {
+                background: Color { a: 0.5, ..SURFACE }.into(),
+                ..self.active()
+            }
+        }
+    }
+
+    pub struct Scrollable;
+
+    impl scrollable::StyleSheet for Scrollable {
+        fn active(&self) -> scrollable::Scrollbar {
+            scrollable::Scrollbar {
+                background: Color {
+                    a: 0.8,
+                    ..SCROLLBAR
+                }
+                .into(),
+                border_radius: 2,
+                border_width: 0,
+                border_color: Color::TRANSPARENT,
+                scroller: scrollable::Scroller {
+                    color: Color { a: 0.7, ..SCROLLER },
+                    border_radius: 2,
+                    border_width: 0,
+                    border_color: Color::TRANSPARENT,
+                },
+            }
+        }
+
+        fn hovered(&self) -> scrollable::Scrollbar {
+            let active = self.active();
+
+            scrollable::Scrollbar {
+                background: SCROLLBAR.into(),
+                scroller: scrollable::Scroller {
+                    color: SCROLLER,
+                    ..active.scroller
+                },
+                ..active
+            }
+        }
+
+        fn dragging(&self) -> scrollable::Scrollbar {
+            let hovered = self.hovered();
+
+            scrollable::Scrollbar {
+                scroller: scrollable::Scroller {
+                    color: ACCENT,
+                    ..hovered.scroller
+                },
+                ..hovered
+            }
+        }
+    }
+
+    pub struct Rule;
+
+    impl rule::StyleSheet for Rule {
+        fn style(&self) -> rule::Style {
+            rule::Style {
+                color: SURFACE,
+                width: 2,
+                radius: 1,
+                fill_mode: rule::FillMode::Percent(30.0),
+            }
+        }
+    }
+}