Clarify CustomScrollView use cases (#189692)
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This updates the `CustomScrollView` API documentation to describe its
common use case more directly: combining different kinds of scrollable
content. The introduction now also calls out `SliverToBoxAdapter`, so
readers can see how regular box widgets fit alongside lists, grids, and
expanding headers.
Fixes #142673.
Tests: not run (documentation-only change; comment-only changes are
automatically test-exempt).
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diff --git a/packages/flutter/lib/src/widgets/scroll_view.dart b/packages/flutter/lib/src/widgets/scroll_view.dart
index fbe1415..8d8f654 100644
--- a/packages/flutter/lib/src/widgets/scroll_view.dart
+++ b/packages/flutter/lib/src/widgets/scroll_view.dart
@@ -587,13 +587,15 @@
}
}
-/// A [ScrollView] that creates custom scroll effects using [slivers].
+/// A [ScrollView] that combines multiple [slivers] in one scrollable view.
///
-/// A [CustomScrollView] lets you supply [slivers] directly to create various
-/// scrolling effects, such as lists, grids, and expanding headers. For example,
-/// to create a scroll view that contains an expanding app bar followed by a
-/// list and a grid, use a list of three slivers: [SliverAppBar], [SliverList],
-/// and [SliverGrid].
+/// A [CustomScrollView] lets you combine lists, grids, and other widgets in a
+/// single scrollable view by supplying [slivers] directly. Slivers can
+/// represent lists, grids, and expanding headers. Widgets that use the box
+/// layout model can be included using a [SliverToBoxAdapter]. For example, to
+/// create a scroll view that contains an expanding app bar followed by a list
+/// and a grid, use a list of three slivers: [SliverAppBar], [SliverList], and
+/// [SliverGrid].
///
/// [Widget]s in these [slivers] must produce [RenderSliver] objects.
///
@@ -716,7 +718,8 @@
/// * [IndexedSemantics], which allows annotating child lists with an index
/// for scroll announcements.
class CustomScrollView extends ScrollView {
- /// Creates a [ScrollView] that creates custom scroll effects using slivers.
+ /// Creates a [ScrollView] that combines multiple slivers in one scrollable
+ /// view.
///
/// See the [ScrollView] constructor for more details on these arguments.
const CustomScrollView({
