AppBarAutoHide class

A widget that automatically hides and shows the AppBar based on scroll events.

This widget wraps an AppBar and listens to scroll notifications to determine whether the AppBar should be visible or hidden. It animates the transition between these states using a fade and size transition.

To use this widget, provide a ValueNotifier that emits scroll notifications from a scrollable widget, such as a ListView or ScrollView. The AppBarAutoHide widget will listen to this notifier and update its state accordingly.

You can customize the behavior of the widget using the following properties:

  • isAutoHide: Whether the AppBar should automatically hide and show.
  • autoHideThreshold: The scroll threshold at which the AppBar should start hiding.
  • animationDuration: The duration of the hide/show animation.
  • leading, title, actions, flexibleSpace, bottom, elevation, scrolledUnderElevation, notificationPredicate, shadowColor, surfaceTintColor, shape, backgroundColor, foregroundColor, iconTheme, actionsIconTheme, primary, centerTitle, excludeHeaderSemantics, titleSpacing, toolbarOpacity, bottomOpacity, toolbarHeight, leadingWidth, toolbarTextStyle, titleTextStyle, systemOverlayStyle, forceMaterialTransparency: These properties are passed directly to the underlying AppBar widget.
Inheritance
Implemented types

Constructors

AppBarAutoHide.new({Key? key, required ValueNotifier<ScrollNotification?> notifier, bool isAutoHide = true, double autoHideThreshold = 200.0, Widget? leading, bool automaticallyImplyLeading = false, Duration animationDuration = const Duration(milliseconds: 300), Widget? title, List<Widget>? actions, Widget? flexibleSpace, PreferredSizeWidget? bottom, double? elevation, double? scrolledUnderElevation, ScrollNotificationPredicate? notificationPredicate, Color? shadowColor, Color? surfaceTintColor, ShapeBorder? shape, Color? backgroundColor, Color? foregroundColor, IconThemeData? iconTheme, IconThemeData? actionsIconTheme, bool primary = true, bool? centerTitle, bool excludeHeaderSemantics = false, double? titleSpacing, double toolbarOpacity = 1.0, double bottomOpacity = 1.0, double? toolbarHeight, double? leadingWidth, TextStyle? toolbarTextStyle, TextStyle? titleTextStyle, SystemUiOverlayStyle? systemOverlayStyle, bool forceMaterialTransparency = false})
Creates an AppBarAutoHide widget.
const

Properties

actions → List<Widget>?
A list of Widgets to display in a row after the title widget.
final
actionsIconTheme → IconThemeData?
The values for the app bar's actions' theme.
final
animationDuration → Duration
The duration of the hide/show animation.
final
autoHideThreshold → double
The scroll threshold at which the AppBar should start hiding.
final
automaticallyImplyLeading → bool
Controls whether we should try to imply the leading widget if null.
final
backgroundColor → Color?
The color to use for the app bar's background.
final
bottom → PreferredSizeWidget?
This widget appears across the bottom of the app bar.
final
bottomOpacity → double
How opaque the bottom part of the app bar is.
final
centerTitle → bool?
Whether the title should be centered.
final
elevation → double?
The z-coordinate at which to place this app bar relative to its parent.
final
excludeHeaderSemantics → bool
Whether the title should be wrapped with header Semantics.
final
flexibleSpace → Widget?
This widget is stacked behind the toolbar and the tab bar.
final
forceMaterialTransparency → bool
Force the AppBar to be Material regardless the theme.
final
foregroundColor → Color?
The default color for Text and Icons within the app bar.
final
hashCode → int
The hash code for this object.
no setterinherited
iconTheme → IconThemeData?
The values for the app bar's theme.
final
isAutoHide → bool
Whether the AppBar should automatically hide and show.
final
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
leading → Widget?
A widget to display before the title.
final
leadingWidth → double?
Defines the width of leading widget.
final
notificationPredicate → ScrollNotificationPredicate?
A check that specifies which kind of scroll notifications should be handled by this widget.
final
notifier → ValueNotifier<ScrollNotification?>
The ValueNotifier that emits scroll notifications.
final
preferredSize → Size
The size this widget would prefer if it were otherwise unconstrained.
no setteroverride
primary → bool
Whether this app bar is being displayed at the top of the screen.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
scrolledUnderElevation → double?
The elevation that the app bar should have when it is scrolled under.
final
shadowColor → Color?
The color to paint the shadow below the app bar.
final
shape → ShapeBorder?
The shape of the app bar's material.
final
surfaceTintColor → Color?
The color to paint the surface behind the app bar.
final
systemOverlayStyle → SystemUiOverlayStyle?
Specifies the system overlays to be placed over the app bar.
final
title → Widget?
The primary widget displayed in the AppBar.
final
titleSpacing → double?
The spacing around title content on the horizontal axis.
final
titleTextStyle → TextStyle?
TextStyle for the AppBar's title widget.
final
toolbarHeight → double?
A size whose height defines the height of the toolbar.
final
toolbarOpacity → double
How opaque the toolbar part of the app bar is.
final
toolbarTextStyle → TextStyle?
Default text style for the AppBar's TextSpans.
final

Methods

createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → _AppBarAutoHideState
Creates the mutable state for this widget at a given location in the tree.
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
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

Operators

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