Refine SheetExtent and related components

example/lib/showcase/ai_playlist_generator.dart

@@ -104,8 +104,8 @@ final _confirmRoute = GoRoute(
   path: 'confirm',
   pageBuilder: (context, state) {
     return const ScrollableNavigationSheetPage(
-      initialExtent: Extent.proportional(0.7),
-      minExtent: Extent.proportional(0.7),
+      initialPosition: SheetAnchor.proportional(0.7),
+      minPosition: SheetAnchor.proportional(0.7),
       physics: BouncingSheetPhysics(
         parent: SnappingSheetPhysics(),
       ),

example/lib/showcase/airbnb_mobile_app.dart

@@ -60,7 +60,7 @@ class _Home extends StatelessWidget {
     return DefaultTabController(
       length: _AppBar.tabs.length,
       // Provides a SheetController to the descendant widgets
-      // to perform some sheet extent driven animations.
+      // to perform some sheet position driven animations.
       // The sheet will look up and use this controller unless
       // another one is manually specified in the constructor.
       // The descendant widgets can also get this controller by
@@ -80,11 +80,11 @@ class _MapButton extends StatelessWidget {
     final sheetController = DefaultSheetController.of(context);
 
     void onPressed() {
-      final metrics = sheetController.value;
+      final metrics = sheetController.metrics;
       if (metrics.hasDimensions) {
         // Collapse the sheet to reveal the map behind.
         sheetController.animateTo(
-          Extent.pixels(metrics.minPixels),
+          SheetAnchor.pixels(metrics.minPixels),
           curve: Curves.fastOutSlowIn,
         );
       }
@@ -97,19 +97,19 @@ class _MapButton extends StatelessWidget {
       icon: const Icon(Icons.map),
     );
 
-    // It is easy to create sheet extent driven animations
-    // by using 'ExtentDrivenAnimation', a special kind of
+    // It is easy to create sheet position driven animations
+    // by using 'PositionDrivenAnimation', a special kind of
     // 'Animation<double>' whose value changes from 0 to 1 as
-    // the sheet extent changes from 'startExtent' to 'endExtent'.
-    final animation = ExtentDrivenAnimation(
+    // the sheet position changes from 'startPosition' to 'endPosition'.
+    final animation = SheetPositionDrivenAnimation(
       controller: DefaultSheetController.of(context),
       // The initial value of the animation is required
-      // since the sheet extent is not available at the first build.
+      // since the sheet position is not available at the first build.
       initialValue: 1,
-      // If null, the minimum extent will be used. (Default)
-      startExtent: null,
-      // If null, the maximum extent will be used. (Default)
-      endExtent: null,
+      // If null, the minimum position will be used. (Default)
+      startPosition: null,
+      // If null, the maximum position will be used. (Default)
+      endPosition: null,
     ).drive(CurveTween(curve: Curves.easeInExpo));
 
     // Hide the button when the sheet is dragged down.
@@ -155,8 +155,8 @@ class _ContentSheet extends StatelessWidget {
         final appbarHeight = MediaQuery.of(context).padding.top;
         final handleHeight = const _ContentSheetHandle().preferredSize.height;
         final sheetHeight = parentHeight - appbarHeight + handleHeight;
-        final minSheetExtent =
-            Extent.pixels(handleHeight + systemUiInsets.bottom);
+        final minSheetPosition =
+            SheetAnchor.pixels(handleHeight + systemUiInsets.bottom);
 
         const sheetShape = RoundedRectangleBorder(
           borderRadius: BorderRadius.vertical(
@@ -168,16 +168,16 @@ class _ContentSheet extends StatelessWidget {
           parent: SnappingSheetPhysics(
             snappingBehavior: SnapToNearest(
               snapTo: [
-                minSheetExtent,
-                const Extent.proportional(1),
+                minSheetPosition,
+                const SheetAnchor.proportional(1),
               ],
             ),
           ),
         );
 
         return ScrollableSheet(
           physics: sheetPhysics,
-          minExtent: minSheetExtent,
+          minPosition: minSheetPosition,
           child: SizedBox(
             height: sheetHeight,
             child: const Card(
@@ -261,7 +261,7 @@ class _HouseList extends StatelessWidget {
 
     // Hide the list when the sheet is dragged down.
     return FadeTransition(
-      opacity: ExtentDrivenAnimation(
+      opacity: SheetPositionDrivenAnimation(
         controller: DefaultSheetController.of(context),
         initialValue: 1,
       ).drive(
@@ -453,7 +453,7 @@ class _BottomNavigationBar extends StatelessWidget {
 
     // Hide the navigation bar when the sheet is dragged down.
     return SlideTransition(
-      position: ExtentDrivenAnimation(
+      position: SheetPositionDrivenAnimation(
         controller: DefaultSheetController.of(context),
         initialValue: 1,
       ).drive(

example/lib/showcase/safari/menu.dart

@@ -22,10 +22,10 @@ class MenuSheet extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    const halfWayExtent = Extent.proportional(0.5);
+    const halfWayPosition = SheetAnchor.proportional(0.5);
     return ScrollableSheet(
-      initialExtent: halfWayExtent,
-      minExtent: halfWayExtent,
+      initialPosition: halfWayPosition,
+      minPosition: halfWayPosition,
       physics: const BouncingSheetPhysics(
         parent: SnappingSheetPhysics(),
       ),
@@ -152,7 +152,7 @@ class _MenuListItem extends StatelessWidget {
       trailing: Icon(icon, color: CupertinoColors.black),
       onTap: () {
         DefaultSheetController.maybeOf(context)
-            ?.animateTo(const Extent.proportional(1));
+            ?.animateTo(const SheetAnchor.proportional(1));
         showEditBookmarkSheet(context);
       },
     );

example/lib/tutorial/bottom_bar_visibility.dart

@@ -133,9 +133,9 @@ class _ExampleSheet extends StatelessWidget {
       ),
     );
 
-    const minSize = Extent.proportional(0.3);
-    const halfSize = Extent.proportional(0.5);
-    const fullSize = Extent.proportional(1);
+    const minSize = SheetAnchor.proportional(0.3);
+    const halfSize = SheetAnchor.proportional(0.5);
+    const fullSize = SheetAnchor.proportional(1);
 
     const multiStopPhysics = BouncingSheetPhysics(
       parent: SnappingSheetPhysics(
@@ -148,8 +148,8 @@ class _ExampleSheet extends StatelessWidget {
     return SafeArea(
       bottom: false,
       child: DraggableSheet(
-        minExtent: minSize,
-        initialExtent: halfSize,
+        minPosition: minSize,
+        initialPosition: halfSize,
         physics: multiStopPhysics,
         child: SheetContentScaffold(
           appBar: AppBar(),
@@ -166,7 +166,7 @@ class _ExampleSheet extends StatelessWidget {
                 getIsVisible: (metrics) {
                   // The bottom bar is visible when at least 50% of the sheet is visible.
                   return metrics.pixels >=
-                      const Extent.proportional(0.5)
+                      const SheetAnchor.proportional(0.5)
                           .resolve(metrics.contentSize);
                 },
                 child: bottomBar,

example/lib/tutorial/bouncing_behaviors.dart

@@ -27,7 +27,7 @@ class _Home extends StatelessWidget {
                   behavior: FixedBouncingBehavior(
                     // Allows the sheet position to exceed the content bounds
                     // by ±10% of the content height.
-                    Extent.proportional(0.1),
+                    SheetAnchor.proportional(0.1),
                   ),
                 ),
               ),
@@ -39,7 +39,7 @@ class _Home extends StatelessWidget {
                 const _DraggableSheet(
                   behavior: FixedBouncingBehavior(
                     // Allows the sheet position to exceed the content bounds by ±50 pixels.
-                    Extent.pixels(50),
+                    SheetAnchor.pixels(50),
                   ),
                 ),
               ),
@@ -53,8 +53,8 @@ class _Home extends StatelessWidget {
                     // Allows the sheet position to exceed the content bounds by 10 pixels
                     // when dragging the sheet upwards, and by ±30% of the content height
                     // when dragging it downwards.
-                    upward: Extent.pixels(20),
-                    downward: Extent.proportional(0.3),
+                    upward: SheetAnchor.pixels(20),
+                    downward: SheetAnchor.proportional(0.3),
                   ),
                 ),
               ),
@@ -66,8 +66,8 @@ class _Home extends StatelessWidget {
                 const _DraggableSheet(
                   behavior: DirectionAwareBouncingBehavior(
                     // Allows the sheet to bounce only when dragging it downwards.
-                    upward: Extent.pixels(0),
-                    downward: Extent.proportional(0.1),
+                    upward: SheetAnchor.pixels(0),
+                    downward: SheetAnchor.proportional(0.1),
                   ),
                 ),
               ),

example/lib/tutorial/cupertino_modal_sheet.dart

@@ -70,10 +70,10 @@ class _HalfScreenSheet extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     // `CupertinoStackedTransition` won't start the transition animation until
-    // the visible height of a modal sheet (the extent) exceeds 50% of the screen height.
+    // the visible height of a modal sheet (the position) exceeds 50% of the screen height.
     return const DraggableSheet(
-      initialExtent: Extent.proportional(0.5),
-      minExtent: Extent.proportional(0.5),
+      initialPosition: SheetAnchor.proportional(0.5),
+      minPosition: SheetAnchor.proportional(0.5),
       physics: BouncingSheetPhysics(
         parent: SnappingSheetPhysics(),
       ),
@@ -120,7 +120,7 @@ class _SheetContent extends StatelessWidget {
                   // `DefaultSheetController.of` is a handy way to obtain a `SheetController`
                   // that is exposed by the parent `CupertinoModalSheetRoute`.
                   DefaultSheetController.maybeOf(context)
-                      ?.animateTo(const Extent.proportional(1));
+                      ?.animateTo(const SheetAnchor.proportional(1));
                   _showModalSheet(context, isFullScreen: true);
                 },
                 child: const Text('Stack'),

example/lib/tutorial/declarative_navigation_sheet.dart

@@ -13,7 +13,7 @@ void main() {
 }
 
 // NavigationSheet requires a special NavigatorObserver in order to
-// smoothly change its extent during a route transition.
+// smoothly change its position during a route transition.
 final transitionObserver = NavigationSheetTransitionObserver();
 
 // To use declarative navigation, we utilize the 'go_router' package.

example/lib/tutorial/extent_driven_animation.dart

@@ -2,11 +2,11 @@ import 'package:flutter/material.dart';
 import 'package:smooth_sheets/smooth_sheets.dart';
 
 void main() {
-  runApp(const _ExtentDrivenAnimationExample());
+  runApp(const _PositionDrivenAnimationExample());
 }
 
-class _ExtentDrivenAnimationExample extends StatelessWidget {
-  const _ExtentDrivenAnimationExample();
+class _PositionDrivenAnimationExample extends StatelessWidget {
+  const _PositionDrivenAnimationExample();
 
   @override
   Widget build(BuildContext context) {
@@ -20,7 +20,7 @@ class _ExampleScaffold extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     // Provides a SheetController to the descendant widgets
-    // to perform some sheet extent driven animations.
+    // to perform some sheet position driven animations.
     // The sheet will look up and use this controller unless
     // another one is manually specified in the constructor.
     // The descendant widgets can also get this controller by
@@ -48,18 +48,18 @@ class _ExampleSheet extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final bottomPadding = MediaQuery.of(context).padding.bottom;
-    final minExtent = Extent.pixels(56 + bottomPadding);
+    final minPosition = SheetAnchor.pixels(56 + bottomPadding);
 
     final physics = BouncingSheetPhysics(
       parent: SnappingSheetPhysics(
         snappingBehavior: SnapToNearest(
-          snapTo: [minExtent, const Extent.proportional(1)],
+          snapTo: [minPosition, const SheetAnchor.proportional(1)],
         ),
       ),
     );
 
     return DraggableSheet(
-      minExtent: minExtent,
+      minPosition: minPosition,
       physics: physics,
       child: Card(
         margin: EdgeInsets.zero,
@@ -84,19 +84,19 @@ class _BottomAppBar extends StatelessWidget {
     // Lookup the nearest controller.
     final controller = DefaultSheetController.of(context);
 
-    // It is easy to create sheet extent driven animations
-    // by using 'ExtentDrivenAnimation', a special kind of
+    // It is easy to create sheet position driven animations
+    // by using 'PositionDrivenAnimation', a special kind of
     // 'Animation<double>' whose value changes from 0 to 1 as
-    // the sheet extent changes from 'startExtent' to 'endExtent'.
-    final animation = ExtentDrivenAnimation(
+    // the sheet position changes from 'startPosition' to 'endPosition'.
+    final animation = SheetPositionDrivenAnimation(
       controller: controller,
       // The initial value of the animation is required
-      // since the sheet extent is not available at the first build.
+      // since the sheet position is not available at the first build.
       initialValue: 1,
-      // If null, the minimum extent will be used. (Default)
-      startExtent: null,
-      // If null, the maximum extent will be used. (Default)
-      endExtent: null,
+      // If null, the minimum position will be used. (Default)
+      startPosition: null,
+      // If null, the maximum position will be used. (Default)
+      endPosition: null,
     );
 
     final bottomAppBar = BottomAppBar(
@@ -134,7 +134,7 @@ class _RotatedFlutterLogo extends StatelessWidget {
   @override
   Widget build(BuildContext context) {
     final logo = RotationTransition(
-      turns: ExtentDrivenAnimation(
+      turns: SheetPositionDrivenAnimation(
         controller: DefaultSheetController.of(context),
         initialValue: 1,
       ),

example/lib/tutorial/imperative_modal_sheet.dart

@@ -67,7 +67,7 @@ class _ExampleSheet extends StatelessWidget {
         }
       },
       child: DraggableSheet(
-        minExtent: const Extent.proportional(0.5),
+        minPosition: const SheetAnchor.proportional(0.5),
         child: Card(
           color: Theme.of(context).colorScheme.secondaryContainer,
           margin: EdgeInsets.zero,

example/lib/tutorial/imperative_navigation_sheet.dart

@@ -22,7 +22,7 @@ class _ImperativeNavigationSheetExample extends StatelessWidget {
 }
 
 // NavigationSheet requires a special NavigatorObserver in order to
-// smoothly change its extent during a route transition.
+// smoothly change its position during a route transition.
 final _transitionObserver = NavigationSheetTransitionObserver();
 
 class _ExampleSheet extends StatelessWidget {

example/lib/tutorial/scrollable_sheet.dart

@@ -45,14 +45,14 @@ class _MySheet extends StatelessWidget {
       child: buildSheetBackground(context, content),
       // Optional: Comment out the following lines to add multiple stop positions.
       //
-      // minExtent: const Extent.proportional(0.2),
+      // minPosition: const SheetAnchor.proportional(0.2),
       // physics: BouncingSheetPhysics(
       //   parent: SnappingSheetPhysics(
       //     snappingBehavior: SnapToNearest(
       //       snapTo: [
-      //         const Extent.proportional(0.2),
-      //         const Extent.proportional(0.5),
-      //         const Extent.proportional(1),
+      //         const SheetAnchor.proportional(0.2),
+      //         const SheetAnchor.proportional(0.5),
+      //         const SheetAnchor.proportional(1),
       //       ],
       //     ),
       //   ),

example/lib/tutorial/sheet_content_scaffold.dart

@@ -44,7 +44,8 @@ class _ExampleSheet extends StatelessWidget {
         getIsVisible: (metrics) {
           return metrics.viewportInsets.bottom == 0 &&
               metrics.pixels >
-                  const Extent.proportional(0.5).resolve(metrics.contentSize);
+                  const SheetAnchor.proportional(0.5)
+                      .resolve(metrics.contentSize);
         },
         child: buildBottomBar(),
       ),
@@ -54,17 +55,17 @@ class _ExampleSheet extends StatelessWidget {
       parent: SnappingSheetPhysics(
         snappingBehavior: SnapToNearest(
           snapTo: [
-            Extent.proportional(0.2),
-            Extent.proportional(0.5),
-            Extent.proportional(1),
+            SheetAnchor.proportional(0.2),
+            SheetAnchor.proportional(0.5),
+            SheetAnchor.proportional(1),
           ],
         ),
       ),
     );
 
     return DraggableSheet(
       physics: physics,
-      minExtent: const Extent.pixels(0),
+      minPosition: const SheetAnchor.pixels(0),
       child: Card(
         clipBehavior: Clip.antiAlias,
         margin: EdgeInsets.zero,