Implement styling for Scrollable

wgpu/src/widget/scrollable.rs

@@ -0,0 +1,13 @@
+//! Navigate an endless amount of content with a scrollbar.
+use crate::Renderer;
+
+pub use iced_native::scrollable::State;
+pub use iced_style::scrollable::{Scrollbar, Scroller, StyleSheet};
+
+/// A widget that can vertically display an infinite amount of content
+/// with a scrollbar.
+///
+/// This is an alias of an `iced_native` scrollable with a default
+/// `Renderer`.
+pub type Scrollable<'a, Message> =
+    iced_native::Scrollable<'a, Message, Renderer>;