HelpButton class
A help button appears within a view and opens app-specific help documentation when clicked. For help documentation creation guidance, see Help. All help buttons are circular, consistently sized buttons that contain a question mark icon. Whenever possible, open a help topic related to the current context. For example, the Rules pane of Mail preferences includes a help button. When clicked, it opens directly to a Rules preferences help topic.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- HelpButton
Constructors
- HelpButton({Key? key, Color? color, Color? disabledColor, VoidCallback? onPressed, double? pressedOpacity = 0.4, AlignmentGeometry alignment = Alignment.center, String? semanticLabel, MouseCursor? mouseCursor = SystemMouseCursors.basic})
-
pressedOpacity, if non-null, must be in the range if 0.0 to 1.0
const
Properties
- alignment → AlignmentGeometry
-
The alignment of the button's
child
.final - color → Color?
-
The color of the button's background.
final
- disabledColor → Color?
-
The color of the button's background when the button is disabled.
final
- enabled → bool
-
Whether the button is enabled or disabled. Buttons are disabled by default. To
enable a button, set its onPressed property to a non-null value.
no setter
- hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- mouseCursor → MouseCursor?
-
The mouse cursor to use when hovering over this widget.
final
- onPressed → VoidCallback?
-
The callback that is called when the button is tapped or otherwise activated.
final
- pressedOpacity → double?
-
The opacity that the button will fade to when it is pressed.
The button will have an opacity of 1.0 when it is not pressed.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- semanticLabel → String?
-
The semantic label used by screen readers.
final
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → HelpButtonState -
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.
override
-
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