Remove ScrollableGrid (#8020)

All the clients have migrated to GridView.  Also, remove RenderGrid,
which isn't needed by GridView.

packages/flutter/lib/rendering.dart

@@ -32,7 +32,6 @@ export 'src/rendering/editable_line.dart';
 export 'src/rendering/error.dart';
 export 'src/rendering/flex.dart';
 export 'src/rendering/flow.dart';
-export 'src/rendering/grid.dart';
 export 'src/rendering/image.dart';
 export 'src/rendering/layer.dart';
 export 'src/rendering/list.dart';

packages/flutter/lib/src/material/list.dart

@@ -55,7 +55,7 @@ Map<MaterialListType, double> kListItemExtent = const <MaterialListType, double>
 ///  * [ScrollableList], on which this widget is based.
 ///  * [TwoLevelList], for lists that have subsections that can collapse and
 ///    expand.
-///  * [ScrollableGrid]
+///  * [GridView]
 ///  * <https://material.google.com/components/lists.html>
 class MaterialList extends StatelessWidget {
   /// Creates a material list.

packages/flutter/lib/src/widgets/basic.dart

@@ -19,19 +19,13 @@ export 'package:flutter/rendering.dart' show
   CrossAxisAlignment,
   CustomClipper,
   CustomPainter,
-  FixedColumnCountGridDelegate,
   FlexFit,
   FlowDelegate,
   FlowPaintingContext,
   FractionalOffsetTween,
-  GridChildPlacement,
-  GridDelegate,
-  GridDelegateWithInOrderChildPlacement,
-  GridSpecification,
   HitTestBehavior,
   MainAxisAlignment,
   MainAxisSize,
-  MaxTileWidthGridDelegate,
   MultiChildLayoutDelegate,
   Overflow,
   PaintingContext,

packages/flutter/lib/src/widgets/lazy_block.dart

@@ -222,7 +222,7 @@ class LazyBlock extends StatelessWidget {
   }
 
   // Warning: keep the dartdoc comments that follow in sync with the copies in
-  // Scrollable, ScrollableGrid, ScrollableViewport, ScrollableList, and
+  // Scrollable, ScrollableViewport, ScrollableList, and
   // ScrollableLazyList. And see: https://github.com/dart-lang/dartdoc/issues/1161.
 
   /// The scroll offset this widget should use when first created.

packages/flutter/lib/src/widgets/scrollable.dart

@@ -375,8 +375,8 @@ typedef double SnapOffsetCallback(double scrollOffset, Size containerSize);
 /// If you have a list of widgets and want them to be able to scroll if there is
 /// insufficient room, consider using [Block].
 ///
-/// Commonly used classes that are based on Scrollable include [ScrollableList],
-/// [ScrollableGrid], and [ScrollableViewport].
+/// Commonly used classes that are based on Scrollable include [ScrollableList]
+/// and [ScrollableViewport].
 ///
 /// Widgets that subclass [Scrollable] typically use state objects that subclass
 /// [ScrollableState].
@@ -400,8 +400,8 @@ class Scrollable extends StatefulWidget {
   }
 
   // Warning: keep the dartdoc comments that follow in sync with the copies in
-  // ScrollableViewport, LazyBlock, ScrollableLazyList, ScrollableList, and
-  // ScrollableGrid. And see: https://github.com/dart-lang/dartdoc/issues/1161.
+  // ScrollableViewport and LazyBlock.
+  // And see: https://github.com/dart-lang/dartdoc/issues/1161.
 
   /// The scroll offset this widget should use when first created.
   final double initialScrollOffset;
@@ -1244,7 +1244,7 @@ class ScrollNotification extends Notification {
 ///
 ///  * [Block], if your single child is a [Column].
 ///  * [ScrollableList], if you have many identically-sized children.
-///  * [ScrollableGrid], if your children are in a grid pattern.
+///  * [GridView], if your children are in a grid pattern.
 ///  * [LazyBlock], if you have many children of varying sizes.
 class ScrollableViewport extends StatelessWidget {
   /// Creates a simple scrolling widget that has a single child.
@@ -1267,8 +1267,8 @@ class ScrollableViewport extends StatelessWidget {
   }
 
   // Warning: keep the dartdoc comments that follow in sync with the copies in
-  // Scrollable, LazyBlock, ScrollableLazyList, ScrollableList, and
-  // ScrollableGrid. And see: https://github.com/dart-lang/dartdoc/issues/1161.
+  // Scrollable, LazyBlock, ScrollableLazyList, and ScrollableList.
+  // And see: https://github.com/dart-lang/dartdoc/issues/1161.
 
   /// The scroll offset this widget should use when first created.
   final double initialScrollOffset;

packages/flutter/lib/src/widgets/scrollable_grid.dart

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-////////////////////////////////////////////////////////////////////////////////
-// DELETE THIS FILE WHEN REMOVING LEGACY SCROLLING CODE
-////////////////////////////////////////////////////////////////////////////////
-
-import 'dart:math' as math;
-
-import 'package:collection/collection.dart' show lowerBound;
-import 'package:flutter/foundation.dart';
-import 'package:flutter/rendering.dart';
-
-import 'framework.dart';
-import 'scroll_configuration.dart';
-import 'scrollable.dart';
-import 'virtual_viewport.dart';
-
-/// A vertically scrollable grid.
-///
-/// Requires that [delegate] places its children in row-major order.
-///
-/// See also:
-///
-///  * [CustomGrid].
-///  * [ScrollableList].
-///  * [ScrollableViewport].
-class ScrollableGrid extends StatelessWidget {
-  /// Creates a vertically scrollable grid.
-  ///
-  /// The [delegate] argument must not be null.
-  ScrollableGrid({
-    Key key,
-    this.initialScrollOffset,
-    this.onScrollStart,
-    this.onScroll,
-    this.onScrollEnd,
-    this.snapOffsetCallback,
-    this.scrollableKey,
-    @required this.delegate,
-    this.children: const <Widget>[],
-  }) : super(key: key) {
-    assert(delegate != null);
-  }
-
-  // Warning: keep the dartdoc comments that follow in sync with the copies in
-  // Scrollable, LazyBlock, ScrollableViewport, ScrollableList, and
-  // ScrollableLazyList. And see: https://github.com/dart-lang/dartdoc/issues/1161.
-
-  /// The scroll offset this widget should use when first created.
-  final double initialScrollOffset;
-
-  /// Called whenever this widget starts to scroll.
-  final ScrollListener onScrollStart;
-
-  /// Called whenever this widget's scroll offset changes.
-  final ScrollListener onScroll;
-
-  /// Called whenever this widget stops scrolling.
-  final ScrollListener onScrollEnd;
-
-  /// Called to determine the offset to which scrolling should snap,
-  /// when handling a fling.
-  ///
-  /// This callback, if set, will be called with the offset that the
-  /// Scrollable would have scrolled to in the absence of this
-  /// callback, and a Size describing the size of the Scrollable
-  /// itself.
-  ///
-  /// The callback's return value is used as the new scroll offset to
-  /// aim for.
-  ///
-  /// If the callback simply returns its first argument (the offset),
-  /// then it is as if the callback was null.
-  final SnapOffsetCallback snapOffsetCallback;
-
-  /// The key for the Scrollable created by this widget.
-  final Key scrollableKey;
-
-  /// The delegate that controls the layout of the children.
-  ///
-  /// For example, a [FixedColumnCountGridDelegate] for grids that have a fixed
-  /// number of columns or a [MaxTileWidthGridDelegate] for grids that have a
-  /// maximum tile width.
-  final GridDelegate delegate;
-
-  /// The children that will be placed in the grid.
-  final Iterable<Widget> children;
-
-  Widget _buildViewport(BuildContext context, ScrollableState state) {
-    return new GridViewport(
-      scrollOffset: state.scrollOffset,
-      delegate: delegate,
-      onExtentsChanged: state.handleExtentsChanged,
-      children: children
-    );
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    final Widget result = new Scrollable(
-      key: scrollableKey,
-      initialScrollOffset: initialScrollOffset,
-      // TODO(abarth): Support horizontal offsets. For horizontally scrolling
-      // grids. For horizontally scrolling grids, we'll probably need to use a
-      // delegate that places children in column-major order.
-      scrollDirection: Axis.vertical,
-      onScrollStart: onScrollStart,
-      onScroll: onScroll,
-      onScrollEnd: onScrollEnd,
-      snapOffsetCallback: snapOffsetCallback,
-      builder: _buildViewport,
-    );
-    return ScrollConfiguration.wrap(context, result);
-  }
-}
-
-/// A virtual viewport onto a grid of widgets.
-///
-/// Used by [ScrollableGrid].
-///
-/// See also:
-///
-///  * [ListViewport].
-///  * [LazyListViewport].
-class GridViewport extends VirtualViewportFromIterable {
-  /// Creates a virtual viewport onto a grid of widgets.
-  ///
-  /// The [delegate] argument must not be null.
-  GridViewport({
-    this.scrollOffset,
-    this.delegate,
-    this.onExtentsChanged,
-    this.children: const <Widget>[],
-  }) {
-    assert(delegate != null);
-  }
-
-  /// The [startOffset] without taking the [delegate]'s padding into account.
-  final double scrollOffset;
-
-  @override
-  double get startOffset {
-    if (delegate == null)
-      return scrollOffset;
-    return scrollOffset - delegate.padding.top;
-  }
-
-  /// The delegate that controls the layout of the children.
-  ///
-  /// For example, a [FixedColumnCountGridDelegate] for grids that have a fixed
-  /// number of columns or a [MaxTileWidthGridDelegate] for grids that have a
-  /// maximum tile width.
-  final GridDelegate delegate;
-
-  /// Called when the interior or exterior dimensions of the viewport change.
-  final ExtentsChangedCallback onExtentsChanged;
-
-  @override
-  final Iterable<Widget> children;
-
-  @override
-  RenderGrid createRenderObject(BuildContext context) => new RenderGrid(delegate: delegate);
-
-  @override
-  _GridViewportElement createElement() => new _GridViewportElement(this);
-}
-
-class _GridViewportElement extends VirtualViewportElement {
-  _GridViewportElement(GridViewport widget) : super(widget);
-
-  @override
-  GridViewport get widget => super.widget;
-
-  @override
-  RenderGrid get renderObject => super.renderObject;
-
-  @override
-  int get materializedChildBase => _materializedChildBase;
-  int _materializedChildBase;
-
-  @override
-  int get materializedChildCount => _materializedChildCount;
-  int _materializedChildCount;
-
-  @override
-  double get startOffsetBase => _startOffsetBase;
-  double _startOffsetBase;
-
-  @override
-  double get startOffsetLimit =>_startOffsetLimit;
-  double _startOffsetLimit;
-
-  @override
-  void updateRenderObject(GridViewport oldWidget) {
-    renderObject.delegate = widget.delegate;
-    super.updateRenderObject(oldWidget);
-  }
-
-  double _lastReportedContentExtent;
-  double _lastReportedContainerExtent;
-  GridSpecification _specification;
-
-  @override
-  void layout(BoxConstraints constraints) {
-    _specification = renderObject.specification;
-    double contentExtent = _specification.gridSize.height;
-    double containerExtent = renderObject.size.height;
-
-    int materializedRowBase = math.max(0, lowerBound(_specification.rowOffsets, widget.startOffset) - 1);
-    int materializedRowLimit = math.min(_specification.rowCount, lowerBound(_specification.rowOffsets, widget.startOffset + containerExtent));
-
-    _materializedChildBase = (materializedRowBase * _specification.columnCount).clamp(0, renderObject.virtualChildCount);
-    _materializedChildCount = (materializedRowLimit * _specification.columnCount).clamp(0, renderObject.virtualChildCount) - _materializedChildBase;
-    _startOffsetBase = _specification.rowOffsets[materializedRowBase];
-    _startOffsetLimit = _specification.rowOffsets[materializedRowLimit] - containerExtent;
-
-    super.layout(constraints);
-
-    if (contentExtent != _lastReportedContentExtent || containerExtent != _lastReportedContainerExtent) {
-      _lastReportedContentExtent = contentExtent;
-      _lastReportedContainerExtent = containerExtent;
-      widget.onExtentsChanged(_lastReportedContentExtent, _lastReportedContainerExtent);
-    }
-  }
-}

packages/flutter/lib/src/widgets/scrollable_list.dart

@@ -61,8 +61,8 @@ class ScrollableList extends StatelessWidget {
   }
 
   // Warning: keep the dartdoc comments that follow in sync with the copies in
-  // Scrollable, LazyBlock, ScrollableLazyList, ScrollableViewport, and
-  // ScrollableGrid. And see: https://github.com/dart-lang/dartdoc/issues/1161.
+  // Scrollable, LazyBlock, ScrollableLazyList, ScrollableViewport.
+  // And see: https://github.com/dart-lang/dartdoc/issues/1161.
 
   /// The scroll offset this widget should use when first created.
   final double initialScrollOffset;
@@ -450,8 +450,8 @@ class ScrollableLazyList extends StatelessWidget {
   }
 
   // Warning: keep the dartdoc comments that follow in sync with the copies in
-  // Scrollable, LazyBlock, ScrollableViewport, ScrollableList, and
-  // ScrollableGrid. And see: https://github.com/dart-lang/dartdoc/issues/1161.
+  // Scrollable, LazyBlock, ScrollableViewport, and ScrollableList.
+  // And see: https://github.com/dart-lang/dartdoc/issues/1161.
 
   /// The scroll offset this widget should use when first created.
   final double initialScrollOffset;

packages/flutter/lib/src/widgets/virtual_viewport.dart

@@ -23,8 +23,7 @@ import 'framework.dart';
 ///    the amount of the thing inside the viewport that is visible from outside
 ///    the viewport).
 ///
-/// Used by [ScrollableGrid.onExtentsChanged],
-/// [ScrollableList.onExtentsChanged], etc.
+/// Used by [ScrollableList.onExtentsChanged], etc.
 typedef void ExtentsChangedCallback(double contentExtent, double containerExtent);
 
 /// An abstract widget whose children are not all materialized.

packages/flutter/lib/widgets.dart

@@ -55,7 +55,6 @@ export 'src/widgets/scroll_position.dart';
 export 'src/widgets/scroll_simulation.dart';
 export 'src/widgets/scroll_view.dart';
 export 'src/widgets/scrollable.dart';
-export 'src/widgets/scrollable_grid.dart';
 export 'src/widgets/scrollable_list.dart';
 export 'src/widgets/semantics_debugger.dart';
 export 'src/widgets/single_child_scroll_view.dart';

packages/flutter/test/rendering/grid_test.dart

-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter/rendering.dart';
-import 'package:test/test.dart';
-
-import 'rendering_tester.dart';
-
-void main() {
-  test('Basic grid layout test', () {
-    List<RenderBox> children = <RenderBox>[
-      new RenderDecoratedBox(decoration: const BoxDecoration()),
-      new RenderDecoratedBox(decoration: const BoxDecoration()),
-      new RenderDecoratedBox(decoration: const BoxDecoration()),
-      new RenderDecoratedBox(decoration: const BoxDecoration())
-    ];
-
-    RenderGrid grid = new RenderGrid(
-      children: children,
-      delegate: new MaxTileWidthGridDelegate(maxTileWidth: 100.0)
-    );
-    layout(grid, constraints: const BoxConstraints(maxWidth: 200.0));
-
-    children.forEach((RenderBox child) {
-      expect(child.size.width, equals(100.0), reason: "child width");
-      expect(child.size.height, equals(100.0), reason: "child height");
-    });
-
-    expect(grid.size.width, equals(200.0), reason: "grid width");
-    expect(grid.size.height, equals(200.0), reason: "grid height");
-
-    expect(grid.debugNeedsLayout, false);
-    grid.delegate = new MaxTileWidthGridDelegate(maxTileWidth: 60.0);
-    expect(grid.debugNeedsLayout, true);
-
-    pumpFrame();
-
-    children.forEach((RenderBox child) {
-      expect(child.size.width, equals(50.0), reason: "child width");
-      expect(child.size.height, equals(50.0), reason: "child height");
-    });
-
-    expect(grid.size.width, equals(200.0), reason: "grid width");
-    expect(grid.size.height, equals(50.0), reason: "grid height");
-  });
-}

packages/flutter/test/widgets/grid_view_layout_test.dart

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/widgets.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  testWidgets('Empty GridView', (WidgetTester tester) async {
+    List<Widget> children = <Widget>[
+      new DecoratedBox(decoration: const BoxDecoration()),
+      new DecoratedBox(decoration: const BoxDecoration()),
+      new DecoratedBox(decoration: const BoxDecoration()),
+      new DecoratedBox(decoration: const BoxDecoration())
+    ];
+
+    await tester.pumpWidget(new Center(
+      child: new Container(
+        width: 200.0,
+        child: new GridView.extent(
+          maxCrossAxisExtent: 100.0,
+          shrinkWrap: true,
+          children: children,
+        ),
+      ),
+    ));
+
+    children.forEach((Widget child) {
+      RenderBox box = tester.renderObject(find.byConfig(child));
+      expect(box.size.width, equals(100.0), reason: "child width");
+      expect(box.size.height, equals(100.0), reason: "child height");
+    });
+
+    RenderBox grid = tester.renderObject(find.byType(GridView));
+    expect(grid.size.width, equals(200.0), reason: "grid width");
+    expect(grid.size.height, equals(200.0), reason: "grid height");
+
+    expect(grid.debugNeedsLayout, false);
+
+    await tester.pumpWidget(new Center(
+      child: new Container(
+        width: 200.0,
+        child: new GridView.extent(
+          maxCrossAxisExtent: 60.0,
+          shrinkWrap: true,
+          children: children,
+        ),
+      ),
+    ));
+
+    children.forEach((Widget child) {
+      RenderBox box = tester.renderObject(find.byConfig(child));
+      expect(box.size.width, equals(50.0), reason: "child width");
+      expect(box.size.height, equals(50.0), reason: "child height");
+    });
+
+    expect(grid.size.width, equals(200.0), reason: "grid width");
+    expect(grid.size.height, equals(50.0), reason: "grid height");
+  });
+}