Documentation updates (#45)

## Changes made

- Add doc comments to `sheet_extent.dart`.
- Avoid using GitHub alert syntax. (Fixes #23)
- Rename `SingleChildSheet*` to `SizedContentSheet*`.

package/CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.3.1 Feb 26, 2024
+
+Documentation updates.
+
 ## 0.3.0 Feb 24, 2024
 
 - Add iOS 15 style modal sheet transition (#21)

package/README.md

@@ -10,13 +10,9 @@
 
 <br/>
 
-> [!CAUTION]
->
-> This library is currently in the experimental stage. The API may undergo changes without prior notice. 
+**CAUTION🚨**
 
-> [!NOTE]
-> 
-> For documentation of the latest published version, please visit the [package site](https://pub.dev/packages/smooth_sheets) on pub.dev.
+This library is currently in the experimental stage. The API may undergo changes without prior notice. For documentation of the latest published version, please visit the [package site](https://pub.dev/packages/smooth_sheets) on pub.dev.
 
 <br/>
 

package/lib/src/draggable/draggable_sheet.dart

@@ -1,8 +1,8 @@
 import 'package:flutter/widgets.dart';
 import 'package:smooth_sheets/smooth_sheets.dart';
-import 'package:smooth_sheets/src/foundation/single_child_sheet.dart';
+import 'package:smooth_sheets/src/foundation/sized_content_sheet.dart';
 
-class DraggableSheet extends SingleChildSheet {
+class DraggableSheet extends SizedContentSheet {
   const DraggableSheet({
     super.key,
     this.hitTestBehavior = HitTestBehavior.translucent,
@@ -18,12 +18,12 @@ class DraggableSheet extends SingleChildSheet {
   final HitTestBehavior hitTestBehavior;
 
   @override
-  SingleChildSheetState<SingleChildSheet> createState() {
+  SizedContentSheetState<SizedContentSheet> createState() {
     return _DraggableSheetState();
   }
 }
 
-class _DraggableSheetState extends SingleChildSheetState<DraggableSheet> {
+class _DraggableSheetState extends SizedContentSheetState<DraggableSheet> {
   @override
   SheetExtentFactory createExtentFactory() {
     return DraggableSheetExtentFactory(
@@ -43,7 +43,7 @@ class _DraggableSheetState extends SingleChildSheetState<DraggableSheet> {
   }
 }
 
-class DraggableSheetExtentFactory extends SingleChildSheetExtentFactory {
+class DraggableSheetExtentFactory extends SizedContentSheetExtentFactory {
   const DraggableSheetExtentFactory({
     required super.initialExtent,
     required super.minExtent,
@@ -63,7 +63,7 @@ class DraggableSheetExtentFactory extends SingleChildSheetExtentFactory {
   }
 }
 
-class DraggableSheetExtent extends SingleChildSheetExtent {
+class DraggableSheetExtent extends SizedContentSheetExtent {
   DraggableSheetExtent({
     required super.context,
     required super.physics,

package/lib/src/draggable/sheet_draggable.dart

@@ -1,15 +1,36 @@
 import 'package:flutter/widgets.dart';
+import 'package:smooth_sheets/src/draggable/draggable_sheet.dart';
 import 'package:smooth_sheets/src/foundation/sheet_activity.dart';
 import 'package:smooth_sheets/src/foundation/sheet_extent.dart';
+import 'package:smooth_sheets/src/scrollable/scrollable_sheet.dart';
 
+/// A widget that makes its child as a drag-handle for a sheet.
+///
+/// Typically, this widget is used when placing non-scrollable widget(s)
+/// in a [ScrollableSheet], since it only works with scrollable widgets,
+/// so you can't drag the sheet by touching a non-scrollable area.
+///
+/// Note that [SheetDraggable] is not needed when using [DraggableSheet]
+/// since it implicitly wraps the child widget with [SheetDraggable].
+///
+/// See also:
+/// - [A tutorial](https://github.com/fujidaiti/smooth_sheets/blob/main/cookbook/lib/tutorial/sheet_draggable.dart),
+///   in which a [SheetDraggable] is used to create a drag-handle for
+///   a [ScrollableSheet].
 class SheetDraggable extends StatefulWidget {
+  /// Creates a drag-handle for a sheet.
+  ///
+  /// The [behavior] defaults to [HitTestBehavior.translucent].
   const SheetDraggable({
     super.key,
     this.behavior = HitTestBehavior.translucent,
     required this.child,
   });
 
+  /// How to behave during hit testing.
   final HitTestBehavior behavior;
+
+  /// The widget below this widget in the tree.
   final Widget child;
 
   @override