SubmenuButton class
A menu button that displays a cascading menu.
It can be used as part of a MenuBar, or as a standalone widget.
This widget represents a menu item that has a submenu. Like the leaf MenuItemButton, it shows a label with an optional leading or trailing icon, but additionally shows an arrow icon showing that it has a submenu.
By default the submenu will appear to the side of the controlling button. The alignment and offset of the submenu can be controlled by setting MenuStyle.alignment on the style and the alignmentOffset argument, respectively.
When activated (by being clicked, through keyboard navigation, or via hovering with a mouse), it will open a submenu containing the menuChildren.
If menuChildren is empty, then this menu item will appear disabled.
See also:
- MenuItemButton, a widget that represents a leaf menu item that does not host a submenu.
- MenuBar, a widget that renders menu items in a row in a Material Design style.
- MenuAnchor, a widget that creates a region with a submenu and shows it when requested.
- PlatformMenuBar, a widget that renders similar menu bar items from a PlatformMenuItem using platform-native APIs instead of Flutter.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- SubmenuButton
Constructors
-
Creates a const SubmenuButton.
const
Properties
- alignmentOffset → Offset?
-
The offset of the menu relative to the alignment origin determined by
MenuStyle.alignment on the style attribute.
final
- child → Widget?
-
The widget displayed in the middle portion of this button.
final
- clipBehavior → Clip
-
The content will be clipped (or not) according to this option.
final
- controller → MenuController?
-
An optional MenuController for this submenu.
final
- focusNode → FocusNode?
-
An optional focus node to use as the focus node for this widget.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- leadingIcon → Widget?
-
An optional icon to display before the child.
final
-
The list of widgets that appear in the menu when it is opened.
final
-
The MenuStyle of the menu specified by menuChildren.
final
- onClose → VoidCallback?
-
A callback that is invoked when the menu is closed.
final
-
onFocusChange
→ ValueChanged<
bool> ? -
Handler called when the focus changes.
final
-
onHover
→ ValueChanged<
bool> ? -
Called when a pointer enters or exits the button response area.
final
- onOpen → VoidCallback?
-
A callback that is invoked when the menu is opened.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- statesController → MaterialStatesController?
-
Represents the interactive "state" of this widget in terms of
a set of WidgetStates, like WidgetState.pressed and
WidgetState.focused.
final
- style → ButtonStyle?
-
Customizes this button's appearance.
final
- trailingIcon → Widget?
-
An optional icon to display after the child.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → State< SubmenuButton> -
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.
override
-
debugFillProperties(
DiagnosticPropertiesBuilder properties) → void -
Add additional properties associated with the node.
override
-
defaultStyleOf(
BuildContext context) → ButtonStyle - Defines the button's default appearance.
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
themeStyleOf(
BuildContext context) → ButtonStyle? - Returns the MenuButtonThemeData.style of the closest MenuButtonTheme ancestor.
-
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
Static Methods
-
styleFrom(
{Color? foregroundColor, Color? backgroundColor, Color? disabledForegroundColor, Color? disabledBackgroundColor, Color? shadowColor, Color? surfaceTintColor, Color? iconColor, double? iconSize, Color? disabledIconColor, TextStyle? textStyle, Color? overlayColor, double? elevation, EdgeInsetsGeometry? padding, Size? minimumSize, Size? fixedSize, Size? maximumSize, MouseCursor? enabledMouseCursor, MouseCursor? disabledMouseCursor, BorderSide? side, OutlinedBorder? shape, VisualDensity? visualDensity, MaterialTapTargetSize? tapTargetSize, Duration? animationDuration, bool? enableFeedback, AlignmentGeometry? alignment, InteractiveInkFeatureFactory? splashFactory}) → ButtonStyle - A static convenience method that constructs a SubmenuButton's ButtonStyle given simple values.