Implement Widget::overlay for Scrollable

native/src/widget/scrollable.rs

@@ -1,7 +1,7 @@
 //! Navigate an endless amount of content with a scrollbar.
 use crate::{
     column, layout, mouse, Align, Clipboard, Column, Element, Event, Hasher,
-    Layout, Length, Point, Rectangle, Size, Widget,
+    Layout, Length, Overlay, Point, Rectangle, Size, Vector, Widget,
 };
 
 use std::{f32, hash::Hash, u32};
@@ -315,6 +315,22 @@ where
 
         self.content.hash_layout(state)
     }
+
+    fn overlay(
+        &mut self,
+        layout: Layout<'_>,
+    ) -> Option<Overlay<'a, Message, Renderer>> {
+        self.content
+            .overlay(layout.children().next().unwrap())
+            .map(|overlay| {
+                let bounds = layout.bounds();
+                let content_layout = layout.children().next().unwrap();
+                let content_bounds = content_layout.bounds();
+                let offset = self.state.offset(bounds, content_bounds);
+
+                overlay.translate(Vector::new(0.0, -(offset as f32)))
+            })
+    }
 }
 
 /// The local state of a [`Scrollable`].