PinnedHeaderSliver class

A sliver that keeps its Widget child at the top of the a CustomScrollView.

This sliver is preferable to the general purpose SliverPersistentHeader for its relatively narrow use case because there's no need to create a SliverPersistentHeaderDelegate or to predict the header's size.

This example demonstrates that the sliver's size can change. Pressing the floating action button replaces the one line of header text with two lines.
link

To create a local project with this code sample, run:
flutter create --sample=widgets.PinnedHeaderSliver.1 mysample

A more elaborate example which creates an app bar that's similar to the one that appears in the iOS Settings app. In this example the pinned header starts out transparent and the first item in the list serves as the app's "Settings" title. When the title item has been scrolled completely behind the pinned header, the header animates its opacity from 0 to 1 and its (centered) "Settings" title appears. The fact that the header's opacity depends on the height of the title item - which is unknown until the list has been laid out - necessitates monitoring the title item's SliverGeometry.scrollExtent and the header's SliverConstraints.scrollOffset from a scroll NotificationListener. See the source code for more details.
link

To create a local project with this code sample, run:
flutter create --sample=widgets.PinnedHeaderSliver.2 mysample

See also:

  • SliverResizingHeader - which similarly pins the header at the top of the CustomScrollView but reacts to scrolling by resizing the header between its minimum and maximum extent limits.
  • SliverFloatingHeader - which animates the header in and out of view in response to downward and upwards scrolls.
  • SliverPersistentHeader - a general purpose header that can be configured as a pinned, resizing, or floating header.
Inheritance

Constructors

PinnedHeaderSliver({Key? key, Widget? child})
Creates a sliver whose Widget child appears at the top of a CustomScrollView.
const

Properties

child → Widget?
The widget below this widget in the tree.
finalinherited
hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

createElement() → SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
createRenderObject(BuildContext context) → RenderObject
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.
override
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
didUnmountRenderObject(covariant RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent 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, int wrapWidth = 65}) → 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
updateRenderObject(BuildContext context, covariant RenderObject renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited