Listener class

A widget that calls callbacks in response to pointer events.

Rather than listening for raw pointer events, consider listening for higher-level gestures using GestureDetector.

Layout behavior

See BoxConstraints for an introduction to box layout models.

If it has a child, this widget defers to the child for sizing behavior. If it does not have a child, it grows to fit the parent instead.

Inheritance

Constructors

Listener({Key key, PointerDownEventListener onPointerDown, PointerMoveEventListener onPointerMove, PointerUpEventListener onPointerUp, PointerCancelEventListener onPointerCancel, HitTestBehavior behavior: HitTestBehavior.deferToChild, Widget child })
Creates a widget that forwards point events to callbacks. [...]
const

Properties

behavior HitTestBehavior
How to behave during hit testing.
final
onPointerCancel PointerCancelEventListener
Called when the input from a pointer that triggered an onPointerDown is no longer directed towards this receiver.
final
onPointerDown PointerDownEventListener
Called when a pointer comes into contact with the screen at this object.
final
onPointerMove PointerMoveEventListener
Called when a pointer that triggered an onPointerDown changes position.
final
onPointerUp PointerUpEventListener
Called when a pointer that triggered an onPointerDown is no longer in contact with the screen.
final
child Widget
The widget below this widget in the tree. [...]
final, inherited
hashCode int
The hash code for this object. [...]
read-only, inherited
key Key
Controls how one widget replaces another widget in the tree. [...]
final, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

createRenderObject(BuildContext context) RenderPointerListener
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget. [...]
override
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
override
updateRenderObject(BuildContext context, covariant RenderPointerListener renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject. [...]
override
createElement() SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
@protected, inherited
didUnmountRenderObject(covariant RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
@protected, inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent 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 toStringDeep. [...]
inherited
toString({DiagnosticLevel minLevel: DiagnosticLevel.debug }) String
Returns 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 ==(dynamic other) bool
The equality operator. [...]
inherited