Tmp

cookbook/lib/showcase/todo_list/todo_editor.dart

@@ -1,3 +1,5 @@
+import 'dart:async';
+
 import 'package:cookbook/showcase/todo_list/models.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
@@ -40,23 +42,28 @@ class _TodoEditorState extends State<TodoEditor> {
       return true;
     }
 
-    // Show a confirmation dialog.
-    showDialog(
-      context: context,
-      builder: (context) {
-        return AlertDialog(
-          title: const Text('Discard changes?'),
-          actions: [
-            TextButton(
-              onPressed: () =>
-                  Navigator.popUntil(context, (route) => route.isFirst),
-              child: const Text('Discard'),
-            ),
-            TextButton(
-              onPressed: () => Navigator.pop(context),
-              child: const Text('Cancel'),
-            ),
-          ],
+    Future.delayed(
+      const Duration(milliseconds: 500),
+      () {
+        // Show a confirmation dialog.
+        showDialog(
+          context: context,
+          builder: (context) {
+            return AlertDialog(
+              title: const Text('Discard changes?'),
+              actions: [
+                TextButton(
+                  onPressed: () =>
+                      Navigator.popUntil(context, (route) => route.isFirst),
+                  child: const Text('Discard'),
+                ),
+                TextButton(
+                  onPressed: () => Navigator.pop(context),
+                  child: const Text('Cancel'),
+                ),
+              ],
+            );
+          },
         );
       },
     );

cookbook/lib/tutorial/imperative_modal_sheet.dart

@@ -55,8 +55,9 @@ class _ExampleSheet extends StatelessWidget {
       // or false otherwise. This is useful when, for example, you want to
       // show a confirmation dialog before dismissing the sheet.
       onDismiss: () {
-        showConfirmDialog(context);
-        return false;
+        // showConfirmDialog(context);
+        // return false;
+        return true;
       },
       child: DraggableSheet(
         child: Card(
@@ -69,6 +70,17 @@ class _ExampleSheet extends StatelessWidget {
             height: 500,
             width: double.infinity,
           ),
+          // child: SizedBox(
+          //   height: 500,
+          //   child: ListView.builder(
+          //     itemCount: 20,
+          //     itemBuilder: (context, index) {
+          //       return ListTile(
+          //         title: Text('Item $index'),
+          //       );
+          //     },
+          //   ),
+          // ),
         ),
       ),
     );

package/lib/src/draggable/sheet_draggable.dart

@@ -2,7 +2,6 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/widgets.dart';
 
-import '../foundation/sheet_drag.dart';
 import '../foundation/sheet_extent.dart';
 import '../scrollable/scrollable_sheet.dart';
 import 'draggable_sheet.dart';
@@ -63,15 +62,7 @@ class _SheetDraggableState extends State<SheetDraggable> {
 
   void _handleDragStart(DragStartDetails details) {
     assert(_currentDrag == null);
-    _currentDrag = _extent?.drag(
-      SheetDragStartDetails(
-        sourceTimeStamp: details.sourceTimeStamp,
-        globalPosition: details.globalPosition,
-        localPosition: details.localPosition,
-        kind: details.kind,
-      ),
-      _disposeDrag,
-    );
+    _currentDrag = _extent?.drag(details, _disposeDrag);
   }
 
   void _handleDragUpdate(DragUpdateDetails details) {

package/lib/src/foundation/sheet_activity.dart

@@ -11,8 +11,17 @@ import 'sheet_status.dart';
 @internal
 @optionalTypeArgs
 abstract class SheetActivity<T extends SheetExtent> {
+  bool _disposed = false;
+  bool get disposed {
+    assert(!_mounted || !_disposed);
+    return _disposed;
+  }
+
   bool _mounted = false;
-  bool get mounted => _mounted;
+  bool get mounted {
+    assert(!_mounted || !_disposed);
+    return _mounted;
+  }
 
   T? _owner;
   T get owner {
@@ -26,10 +35,9 @@ abstract class SheetActivity<T extends SheetExtent> {
 
   @mustCallSuper
   void init(T owner) {
-    assert(
-      _owner == null,
-      'init() must be called only once.',
-    );
+    assert(_owner == null);
+    assert(!_mounted);
+    assert(!_disposed);
 
     _owner = owner;
     _mounted = true;
@@ -42,6 +50,7 @@ abstract class SheetActivity<T extends SheetExtent> {
 
   void dispose() {
     _mounted = false;
+    _disposed = true;
   }
 
   bool isCompatibleWith(SheetExtent newOwner) => newOwner is T;
@@ -102,6 +111,20 @@ abstract class SheetActivity<T extends SheetExtent> {
     }());
     return true;
   }
+
+  @protected
+  bool debugAssertNotDisposed() {
+    assert(() {
+      if (disposed) {
+        throw FlutterError(
+          'A $runtimeType was used after being disposed. Once you have '
+          'called dispose() on a $runtimeType, it can no longer be used.',
+        );
+      }
+      return true;
+    }());
+    return true;
+  }
 }
 
 @internal
@@ -170,14 +193,32 @@ class IdleSheetActivity extends SheetActivity {
 @internal
 class DragSheetActivity extends SheetActivity
     with UserControlledSheetActivityMixin
-    implements SheetDragControllerDelegate {
+    implements SheetDragControllerTarget {
   DragSheetActivity();
 
   @override
-  AxisDirection get dragAxisDirection => AxisDirection.up;
+  VerticalDirection get dragAxisDirection => VerticalDirection.up;
+
+  @override
+  Offset computeMinPotentialDeltaConsumption(Offset delta) {
+    final metrics = owner.metrics;
+
+    switch (delta.dy) {
+      case > 0:
+        final draggableDistance = max(0.0, metrics.maxPixels - metrics.pixels);
+        return Offset(delta.dx, min(draggableDistance, delta.dy));
+
+      case < 0:
+        final draggableDistance = max(0.0, metrics.minPixels - metrics.pixels);
+        return Offset(delta.dx, max(-1 * draggableDistance, delta.dy));
+
+      case _:
+        return delta;
+    }
+  }
 
   @override
-  void onDragUpdate(SheetDragUpdateDetails details) {
+  void applyUserDragUpdate(SheetDragUpdateDetails details) {
     final physicsAppliedDelta = owner.config.physics
         .applyPhysicsToOffset(details.primaryDelta, owner.metrics);
     if (physicsAppliedDelta != 0) {
@@ -186,7 +227,7 @@ class DragSheetActivity extends SheetActivity
   }
 
   @override
-  void onDragEnd(SheetDragEndDetails details) {
+  void applyUserDragEnd(SheetDragEndDetails details) {
     owner.goBallistic(details.primaryVelocity);
   }
 }