MaterialBanner class
A Material Design banner.
A banner displays an important, succinct message, and provides actions for users to address (or dismiss the banner). A user action is required for it to be dismissed.
Banners should be displayed at the top of the screen, below a top app bar. They are persistent and non-modal, allowing the user to either ignore them or interact with them at any time.
To create a local project with this code sample, run:
flutter create --sample=material.MaterialBanner.1 mysample
To create a local project with this code sample, run:
flutter create --sample=material.MaterialBanner.2 mysample
The actions will be placed beside the content if there is only one. Otherwise, the actions will be placed below the content. Use forceActionsBelow to override this behavior.
If the actions placed below the content, they will be laid out in a row. If there isn't sufficient room to display everything, they are laid out in a column instead.
The actions and content must be provided. An optional leading widget (typically an Image) can also be provided. The contentTextStyle and backgroundColor can be provided to customize the banner.
This widget is unrelated to the widgets library Banner widget.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- MaterialBanner
Constructors
-
MaterialBanner({Key? key, required Widget content, TextStyle? contentTextStyle, required List<
Widget> actions, double? elevation, Widget? leading, Color? backgroundColor, Color? surfaceTintColor, Color? shadowColor, Color? dividerColor, EdgeInsetsGeometry? padding, EdgeInsetsGeometry? margin, EdgeInsetsGeometry? leadingPadding, bool forceActionsBelow = false, OverflowBarAlignment overflowAlignment = OverflowBarAlignment.end, Animation<double> ? animation, VoidCallback? onVisible, double minActionBarHeight = 52.0}) -
Creates a MaterialBanner.
const
Properties
-
actions
→ List<
Widget> -
The set of actions that are displayed at the bottom or trailing side of
the MaterialBanner.
final
-
animation
→ Animation<
double> ? -
The animation driving the entrance and exit of the material banner when presented by the ScaffoldMessenger.
final
- backgroundColor → Color?
-
The color of the surface of this MaterialBanner.
final
- content → Widget
-
The content of the MaterialBanner.
final
- contentTextStyle → TextStyle?
-
Style for the text in the content of the MaterialBanner.
final
- dividerColor → Color?
-
The color of the divider.
final
- elevation → double?
-
The z-coordinate at which to place the material banner.
final
- forceActionsBelow → bool
-
An override to force the actions to be below the content regardless of
how many there are.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- leading → Widget?
-
The (optional) leading widget of the MaterialBanner.
final
- leadingPadding → EdgeInsetsGeometry?
-
The amount of space by which to inset the leading widget.
final
- margin → EdgeInsetsGeometry?
-
Empty space to surround the MaterialBanner.
final
- minActionBarHeight → double
-
The optional minimum action bar height.
final
- onVisible → VoidCallback?
-
Called the first time that the material banner is visible within a Scaffold when presented by the ScaffoldMessenger.
final
- overflowAlignment → OverflowBarAlignment
-
The horizontal alignment of the actions when the actions laid out in a column.
final
- padding → EdgeInsetsGeometry?
-
The amount of space by which to inset the content.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- shadowColor → Color?
-
The color of the shadow below the MaterialBanner.
final
- surfaceTintColor → Color?
-
The color used as an overlay on backgroundColor to indicate elevation.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → State< MaterialBanner> -
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
-
withAnimation(
Animation< double> newAnimation, {Key? fallbackKey}) → MaterialBanner - Creates a copy of this material banner but with the animation replaced with the given animation.
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited
Static Methods
-
createAnimationController(
{required TickerProvider vsync}) → AnimationController - Creates an animation controller useful for driving a MaterialBanner's entrance and exit animation.