PopupMenuButton<T> class
Displays a menu when pressed and calls onSelected when the menu is dismissed because an item was selected. The value passed to onSelected is the value of the selected menu item.
One of child or icon may be provided, but not both. If icon is provided, then PopupMenuButton behaves like an IconButton.
If both are null, then a standard overflow icon is created (depending on the platform).
{@tool snippet}
This example shows a menu with four items, selecting between an enum's
values and setting a _selection
field based on the selection.
// This is the type used by the popup menu below.
enum WhyFarther { harder, smarter, selfStarter, tradingCharter }
// This menu button widget updates a _selection field (of type WhyFarther,
// not shown here).
PopupMenuButton<WhyFarther>(
onSelected: (WhyFarther result) { setState(() { _selection = result; }); },
itemBuilder: (BuildContext context) => <PopupMenuEntry<WhyFarther>>[
const PopupMenuItem<WhyFarther>(
value: WhyFarther.harder,
child: Text('Working a lot harder'),
),
const PopupMenuItem<WhyFarther>(
value: WhyFarther.smarter,
child: Text('Being a lot smarter'),
),
const PopupMenuItem<WhyFarther>(
value: WhyFarther.selfStarter,
child: Text('Being a self-starter'),
),
const PopupMenuItem<WhyFarther>(
value: WhyFarther.tradingCharter,
child: Text('Placed in charge of trading charter'),
),
],
)
{@end-tool}
See also:
- PopupMenuItem, a popup menu entry for a single value.
- PopupMenuDivider, a popup menu entry that is just a horizontal line.
- CheckedPopupMenuItem, a popup menu item with a checkmark.
- showMenu, a method to dynamically show a popup menu at a given location.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- PopupMenuButton
Constructors
-
PopupMenuButton({Key? key, required PopupMenuItemBuilder<
T> itemBuilder, T? initialValue, PopupMenuItemSelected<T> ? onSelected, PopupMenuCanceled? onCanceled, String? tooltip, double? elevation, EdgeInsetsGeometry padding = const EdgeInsets.all(8.0), Widget? child, Widget? icon, Offset offset = Offset.zero, bool enabled = true, ShapeBorder? shape, Color? color, bool captureInheritedThemes = true}) -
Creates a button that shows a popup menu.
const
Properties
- captureInheritedThemes → bool
-
If true (the default) then the menu will be wrapped with copies
of the
InheritedThemes
, like Theme and PopupMenuTheme, which are defined above the BuildContext where the menu is shown.final - child → Widget?
-
If provided, child is the widget used for this button
and the button will utilize an InkWell for taps.
final
- color → Color?
-
If provided, the background color used for the menu.
final
- elevation → double?
-
The z-coordinate at which to place the menu when open. This controls the
size of the shadow below the menu.
final
- enabled → bool
-
Whether this popup menu button is interactive.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- icon → Widget?
-
If provided, the icon is used for this button
and the button will behave like an IconButton.
final
- initialValue → T?
-
The value of the menu item, if any, that should be highlighted when the menu opens.
final
-
itemBuilder
→ PopupMenuItemBuilder<
T> -
Called when the button is pressed to create the items to show in the menu.
final
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- offset → Offset
-
The offset applied to the Popup Menu Button.
final
- onCanceled → PopupMenuCanceled?
-
Called when the user dismisses the popup menu without selecting an item.
final
-
onSelected
→ PopupMenuItemSelected<
T> ? -
Called when the user selects a value from the popup menu created by this button.
final
- padding → EdgeInsetsGeometry
-
Matches IconButton's 8 dps padding by default. In some cases, notably where
this button appears as the trailing element of a list item, it's useful to be able
to set the padding to zero.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- shape → ShapeBorder?
-
If provided, the shape used for the menu.
final
- tooltip → String?
-
Text that describes the action that will occur when the button is pressed.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → PopupMenuButtonState< T> -
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}) → 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