GridView class Null safety

A scrollable, 2D array of widgets.

The main axis direction of a grid is the direction in which it scrolls (the scrollDirection).

The most commonly used grid layouts are GridView.count, which creates a layout with a fixed number of tiles in the cross axis, and GridView.extent, which creates a layout with tiles that have a maximum cross-axis extent. A custom SliverGridDelegate can produce an arbitrary 2D arrangement of children, including arrangements that are unaligned or overlapping.

To create a grid with a large (or infinite) number of children, use the GridView.builder constructor with either a SliverGridDelegateWithFixedCrossAxisCount or a SliverGridDelegateWithMaxCrossAxisExtent for the gridDelegate.

To use a custom SliverChildDelegate, use GridView.custom.

To create a linear array of children, use a ListView.

To control the initial scroll offset of the scroll view, provide a controller with its ScrollController.initialScrollOffset property set.

Transitioning to CustomScrollView

A GridView is basically a CustomScrollView with a single SliverGrid in its CustomScrollView.slivers property.

If GridView is no longer sufficient, for example because the scroll view is to have both a grid and a list, or because the grid is to be combined with a SliverAppBar, etc, it is straight-forward to port code from using GridView to using CustomScrollView directly.

The key, scrollDirection, reverse, controller, primary, physics, and shrinkWrap properties on GridView map directly to the identically named properties on CustomScrollView.

The CustomScrollView.slivers property should be a list containing just a SliverGrid.

The childrenDelegate property on GridView corresponds to the SliverGrid.delegate property, and the gridDelegate property on the GridView corresponds to the SliverGrid.gridDelegate property.

The GridView, GridView.count, and GridView.extent constructors' children arguments correspond to the childrenDelegate being a SliverChildListDelegate with that same argument. The GridView.builder constructor's itemBuilder and childCount arguments correspond to the childrenDelegate being a SliverChildBuilderDelegate with the matching arguments.

The GridView.count and GridView.extent constructors create custom grid delegates, and have equivalently named constructors on SliverGrid to ease the transition: SliverGrid.count and SliverGrid.extent respectively.

The padding property corresponds to having a SliverPadding in the CustomScrollView.slivers property instead of the grid itself, and having the SliverGrid instead be a child of the SliverPadding.

Once code has been ported to use CustomScrollView, other slivers, such as SliverList or SliverAppBar, can be put in the CustomScrollView.slivers list.

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This example demonstrates how to create a GridView with two columns. The children are spaced apart using the crossAxisSpacing and mainAxisSpacing properties.

The GridView displays six children with different background colors arranged in two columns 

GridView.count(
  primary: false,
  padding: const EdgeInsets.all(20),
  crossAxisSpacing: 10,
  mainAxisSpacing: 10,
  crossAxisCount: 2,
  children: <Widget>[
    Container(
      padding: const EdgeInsets.all(8),
      color: Colors.teal[100],
      child: const Text("He'd have you all unravel at the"),
    ),
    Container(
      padding: const EdgeInsets.all(8),
      color: Colors.teal[200],
      child: const Text('Heed not the rabble'),
    ),
    Container(
      padding: const EdgeInsets.all(8),
      color: Colors.teal[300],
      child: const Text('Sound of screams but the'),
    ),
    Container(
      padding: const EdgeInsets.all(8),
      color: Colors.teal[400],
      child: const Text('Who scream'),
    ),
    Container(
      padding: const EdgeInsets.all(8),
      color: Colors.teal[500],
      child: const Text('Revolution is coming...'),
    ),
    Container(
      padding: const EdgeInsets.all(8),
      color: Colors.teal[600],
      child: const Text('Revolution, they...'),
    ),
  ],
)

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This example shows how to create the same grid as the previous example using a CustomScrollView and a SliverGrid.

The CustomScrollView contains a SliverGrid that displays six children with different background colors arranged in two columns 

CustomScrollView(
  primary: false,
  slivers: <Widget>[
    SliverPadding(
      padding: const EdgeInsets.all(20),
      sliver: SliverGrid.count(
        crossAxisSpacing: 10,
        mainAxisSpacing: 10,
        crossAxisCount: 2,
        children: <Widget>[
          Container(
            padding: const EdgeInsets.all(8),
            color: Colors.green[100],
            child: const Text("He'd have you all unravel at the"),
          ),
          Container(
            padding: const EdgeInsets.all(8),
            color: Colors.green[200],
            child: const Text('Heed not the rabble'),
          ),
          Container(
            padding: const EdgeInsets.all(8),
            color: Colors.green[300],
            child: const Text('Sound of screams but the'),
          ),
          Container(
            padding: const EdgeInsets.all(8),
            color: Colors.green[400],
            child: const Text('Who scream'),
          ),
          Container(
            padding: const EdgeInsets.all(8),
            color: Colors.green[500],
            child: const Text('Revolution is coming...'),
          ),
          Container(
            padding: const EdgeInsets.all(8),
            color: Colors.green[600],
            child: const Text('Revolution, they...'),
          ),
        ],
      ),
    ),
  ],
)

By default, GridView will automatically pad the limits of the grids's scrollable to avoid partial obstructions indicated by MediaQuery's padding. To avoid this behavior, override with a zero padding property.

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The following example demonstrates how to override the default top padding using MediaQuery.removePadding. 
Widget myWidget(BuildContext context) {
  return MediaQuery.removePadding(
    context: context,
    removeTop: true,
    child: GridView.builder(
      gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
        crossAxisCount: 3,
      ),
      itemCount: 300,
      itemBuilder: (BuildContext context, int index) {
        return Card(
          color: Colors.amber,
          child: Center(child: Text('$index')),
        );
      }
    ),
  );
}

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This example shows a custom implementation of ListTile selection in a GridView or ListView. Long press any ListTile to enable selection mode.
To create a local project with this code sample, run:
flutter create --sample=widgets.GridView.4 mysample

See also:

Inheritance

Constructors

GridView({Key? key, Axis scrollDirection = Axis.vertical, bool reverse = false, ScrollController? controller, bool? primary, ScrollPhysics? physics, bool shrinkWrap = false, EdgeInsetsGeometry? padding, required SliverGridDelegate gridDelegate, bool addAutomaticKeepAlives = true, bool addRepaintBoundaries = true, bool addSemanticIndexes = true, double? cacheExtent, List<Widget> children = const <Widget>[], int? semanticChildCount, DragStartBehavior dragStartBehavior = DragStartBehavior.start, Clip clipBehavior = Clip.hardEdge, ScrollViewKeyboardDismissBehavior keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual, String? restorationId})
Creates a scrollable, 2D array of widgets with a custom SliverGridDelegate.
GridView.builder({Key? key, Axis scrollDirection = Axis.vertical, bool reverse = false, ScrollController? controller, bool? primary, ScrollPhysics? physics, bool shrinkWrap = false, EdgeInsetsGeometry? padding, required SliverGridDelegate gridDelegate, required IndexedWidgetBuilder itemBuilder, ChildIndexGetter? findChildIndexCallback, int? itemCount, bool addAutomaticKeepAlives = true, bool addRepaintBoundaries = true, bool addSemanticIndexes = true, double? cacheExtent, int? semanticChildCount, DragStartBehavior dragStartBehavior = DragStartBehavior.start, ScrollViewKeyboardDismissBehavior keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual, String? restorationId, Clip clipBehavior = Clip.hardEdge})
Creates a scrollable, 2D array of widgets that are created on demand.
GridView.count({Key? key, Axis scrollDirection = Axis.vertical, bool reverse = false, ScrollController? controller, bool? primary, ScrollPhysics? physics, bool shrinkWrap = false, EdgeInsetsGeometry? padding, required int crossAxisCount, double mainAxisSpacing = 0.0, double crossAxisSpacing = 0.0, double childAspectRatio = 1.0, bool addAutomaticKeepAlives = true, bool addRepaintBoundaries = true, bool addSemanticIndexes = true, double? cacheExtent, List<Widget> children = const <Widget>[], int? semanticChildCount, DragStartBehavior dragStartBehavior = DragStartBehavior.start, ScrollViewKeyboardDismissBehavior keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual, String? restorationId, Clip clipBehavior = Clip.hardEdge})
Creates a scrollable, 2D array of widgets with a fixed number of tiles in the cross axis.
GridView.custom({Key? key, Axis scrollDirection = Axis.vertical, bool reverse = false, ScrollController? controller, bool? primary, ScrollPhysics? physics, bool shrinkWrap = false, EdgeInsetsGeometry? padding, required SliverGridDelegate gridDelegate, required SliverChildDelegate childrenDelegate, double? cacheExtent, int? semanticChildCount, DragStartBehavior dragStartBehavior = DragStartBehavior.start, ScrollViewKeyboardDismissBehavior keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual, String? restorationId, Clip clipBehavior = Clip.hardEdge})
Creates a scrollable, 2D array of widgets with both a custom SliverGridDelegate and a custom SliverChildDelegate.
const
GridView.extent({Key? key, Axis scrollDirection = Axis.vertical, bool reverse = false, ScrollController? controller, bool? primary, ScrollPhysics? physics, bool shrinkWrap = false, EdgeInsetsGeometry? padding, required double maxCrossAxisExtent, double mainAxisSpacing = 0.0, double crossAxisSpacing = 0.0, double childAspectRatio = 1.0, bool addAutomaticKeepAlives = true, bool addRepaintBoundaries = true, bool addSemanticIndexes = true, double? cacheExtent, List<Widget> children = const <Widget>[], int? semanticChildCount, DragStartBehavior dragStartBehavior = DragStartBehavior.start, ScrollViewKeyboardDismissBehavior keyboardDismissBehavior = ScrollViewKeyboardDismissBehavior.manual, String? restorationId, Clip clipBehavior = Clip.hardEdge})
Creates a scrollable, 2D array of widgets with tiles that each have a maximum cross-axis extent.

Properties

anchor → double
The relative position of the zero scroll offset.
finalinherited
cacheExtent → double?
The viewport has an area before and after the visible area to cache items that are about to become visible when the user scrolls.
finalinherited
center → Key?
The first child in the GrowthDirection.forward growth direction.
finalinherited
childrenDelegate → SliverChildDelegate
A delegate that provides the children for the GridView.
final
clipBehavior → Clip
The content will be clipped (or not) according to this option.
finalinherited
controller → ScrollController?
An object that can be used to control the position to which this scroll view is scrolled.
finalinherited
dragStartBehavior → DragStartBehavior
Determines the way that drag start behavior is handled.
finalinherited
gridDelegate → SliverGridDelegate
A delegate that controls the layout of the children within the GridView.
final
hashCode → int
The hash code for this object.
nonVirtual">@nonVirtualread-onlyinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
keyboardDismissBehavior → ScrollViewKeyboardDismissBehavior
ScrollViewKeyboardDismissBehavior the defines how this ScrollView will dismiss the keyboard automatically.
finalinherited
padding → EdgeInsetsGeometry?
The amount of space by which to inset the children.
finalinherited
physics → ScrollPhysics?
How the scroll view should respond to user input.
finalinherited
primary → bool?
Whether this is the primary scroll view associated with the parent PrimaryScrollController.
finalinherited
restorationId → String?
Restoration ID to save and restore the scroll offset of the scrollable.
finalinherited
reverse → bool
Whether the scroll view scrolls in the reading direction.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited
scrollBehavior → ScrollBehavior?
A ScrollBehavior that will be applied to this widget individually.
finalinherited
scrollDirection → Axis
The axis along which the scroll view scrolls.
finalinherited
semanticChildCount → int?
The number of children that will contribute semantic information.
finalinherited
shrinkWrap → bool
Whether the extent of the scroll view in the scrollDirection should be determined by the contents being viewed.
finalinherited

Methods

build(BuildContext context) → Widget
Describes the part of the user interface represented by this widget.
inherited
buildChildLayout(BuildContext context) → Widget
Subclasses should override this method to build the layout model.
override
buildSlivers(BuildContext context) → List<Widget>
Build the list of widgets to place inside the viewport.
inherited
buildViewport(BuildContext context, ViewportOffset offset, AxisDirection axisDirection, List<Widget> slivers) → Widget
Build the viewport.
protected">@protectedinherited
createElement() → StatelessElement
Creates a StatelessElement to manage this widget's location in the tree.
inherited
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
protected">@protectedinherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
getDirection(BuildContext context) → AxisDirection
Returns the AxisDirection in which the scroll view scrolls.
protected">@protectedinherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String
A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a one-line detailed description of the object.
inherited
toStringShort() → String
A short, textual description of this widget.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
nonVirtual">@nonVirtualinherited