MaterialScrollBehavior class
Describes how Scrollable widgets behave for MaterialApps.
Used by ScrollConfiguration to configure the Scrollable widgets in a subtree.
This class can be extended to further customize a ScrollBehavior for a subtree. For example, overriding ScrollBehavior.getScrollPhysics sets the default ScrollPhysics for Scrollables that inherit this ScrollConfiguration. Overriding ScrollBehavior.buildOverscrollIndicator can be used to add or change the default GlowingOverscrollIndicator decoration, while ScrollBehavior.buildScrollbar can be changed to modify the default Scrollbar.
When looking to easily toggle the default decorations, you can use
ScrollBehavior.copyWith instead of creating your own ScrollBehavior class.
The scrollbar and overscrollIndicator flags can turn these decorations off.
Setting a MaterialScrollBehavior will apply a GlowingOverscrollIndicator to Scrollable descendants when executing on TargetPlatform.android and TargetPlatform.fuchsia.
When using the desktop platform, if the Scrollable widget scrolls in the Axis.vertical, a Scrollbar is applied.
If the scroll direction is Axis.horizontal scroll views are less discoverable, so consider adding a Scrollbar in these cases, either directly or through the buildScrollbar method.
ThemeData.useMaterial3 specifies the overscroll indicator that is used on TargetPlatform.android, which defaults to true, resulting in a StretchingOverscrollIndicator. Setting ThemeData.useMaterial3 to false will instead use a GlowingOverscrollIndicator.
See also:
- ScrollBehavior, the default scrolling behavior extended by this class.
- Inheritance
-
- Object
- ScrollBehavior
- MaterialScrollBehavior
Constructors
- MaterialScrollBehavior()
-
Creates a MaterialScrollBehavior that decorates Scrollables with
StretchingOverscrollIndicators and Scrollbars based on the current
platform and provided ScrollableDetails.
const
Properties
-
dragDevices
→ Set<
PointerDeviceKind> -
The device kinds that the scrollable will accept drag gestures from.
no setterinherited
- hashCode → int
-
The hash code for this object.
no setterinherited
-
pointerAxisModifiers
→ Set<
LogicalKeyboardKey> -
A set of LogicalKeyboardKeys that, when any or all are pressed in
combination with a PointerDeviceKind.mouse pointer scroll event, will
flip the axes of the scroll input.
no setterinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
buildOverscrollIndicator(
BuildContext context, Widget child, ScrollableDetails details) → Widget -
Applies a GlowingOverscrollIndicator to the child widget on
TargetPlatform.android and TargetPlatform.fuchsia.
override
-
buildScrollbar(
BuildContext context, Widget child, ScrollableDetails details) → Widget -
Applies a RawScrollbar to the child widget on desktop platforms.
override
-
copyWith(
{bool? scrollbars, bool? overscroll, Set< PointerDeviceKind> ? dragDevices, MultitouchDragStrategy? multitouchDragStrategy, Set<LogicalKeyboardKey> ? pointerAxisModifiers, ScrollPhysics? physics, TargetPlatform? platform}) → ScrollBehavior -
Creates a copy of this ScrollBehavior, making it possible to
easily toggle
scrollbarandoverscrollIndicatoreffects.inherited -
getMultitouchDragStrategy(
BuildContext context) → MultitouchDragStrategy -
Configure the multi-finger drag strategy on multi-touch devices.
inherited
-
getPlatform(
BuildContext context) → TargetPlatform -
The platform whose scroll physics should be implemented.
override
-
getScrollPhysics(
BuildContext context) → ScrollPhysics -
The scroll physics to use for the platform given by getPlatform.
inherited
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
shouldNotify(
covariant ScrollBehavior oldDelegate) → bool -
Called whenever a ScrollConfiguration is rebuilt with a new
ScrollBehavior of the same runtimeType.
inherited
-
toString(
) → String -
A string representation of this object.
inherited
-
velocityTrackerBuilder(
BuildContext context) → GestureVelocityTrackerBuilder -
Specifies the type of velocity tracker to use in the descendant
Scrollables' drag gesture recognizers, for estimating the velocity of a
drag gesture.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited