ScrollMetricsNotification class
A notification that a scrollable widget's ScrollMetrics have changed.
For example, when the content of a scrollable is altered, making it larger or smaller, this notification will be dispatched. Similarly, if the size of the window or parent changes, the scrollable can notify of these changes in dimensions.
The above behaviors usually do not trigger ScrollNotification events, so this is useful for listening to ScrollMetrics changes that are not caused by the user scrolling.
This sample shows how a ScrollMetricsNotification is dispatched when
the
link
windowSize is changed. Press the floating action button to increase
the scrollable window's size.
To create a local project with this code sample, run:
flutter create --sample=widgets.ScrollMetricsNotification.1 mysample
- Inheritance
-
- Object
- Notification
- ScrollMetricsNotification
- Mixed-in types
Constructors
- ScrollMetricsNotification({required ScrollMetrics metrics, required BuildContext context})
- Creates a notification that the scrollable widget's ScrollMetrics have changed.
Properties
- context → BuildContext
-
The build context of the widget that fired this notification.
final
- depth → int
-
The number of viewports that this notification has bubbled through.
no setterinherited
- hashCode → int
-
The hash code for this object.
no setterinherited
- metrics → ScrollMetrics
-
Description of a scrollable widget's ScrollMetrics.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
asScrollUpdate(
) → ScrollUpdateNotification - Convert this notification to a ScrollNotification.
-
debugFillDescription(
List< String> description) → void -
Add additional information to the given description for use by toString.
override
-
dispatch(
BuildContext? target) → void -
Start bubbling this notification at the given build context.
inherited
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
toString(
) → String -
A string representation of this object.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited