MultiDragGestureRecognizer<T extends MultiDragPointerState> class Null safety

Recognizes movement on a per-pointer basis.

In contrast to DragGestureRecognizer, MultiDragGestureRecognizer watches each pointer separately, which means multiple drags can be recognized concurrently if multiple pointers are in contact with the screen.

MultiDragGestureRecognizer is not intended to be used directly. Instead, consider using one of its subclasses to recognize specific types for drag gestures.

See also:

Inheritance
Implementers

Constructors

MultiDragGestureRecognizer({required Object? debugOwner, PointerDeviceKind? kind})
Initialize the object.

Properties

debugDescription String
Returns a very short pretty description of the gesture that the recognizer looks for, like 'tap' or 'horizontal drag'.
read-only, inherited
debugOwner Object?
The recognizer's owner. [...]
final, inherited
hashCode int
The hash code for this object. [...]
read-only, inherited
onStart GestureMultiDragStartCallback?
Called when this class recognizes the start of a drag gesture. [...]
read / write
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

acceptGesture(int pointer) → void
Called when this member wins the arena for the given pointer id.
override
addAllowedPointer(PointerDownEvent event) → void
Registers a new pointer that's been checked to be allowed by this gesture recognizer. [...]
override
addPointer(PointerDownEvent event) → void
Registers a new pointer that might be relevant to this gesture detector. [...]
inherited
createNewPointerState(PointerDownEvent event) → T
Subclasses should override this method to create per-pointer state objects to track the pointer associated with the given event.
@factory, @protected
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
dispose() → void
Releases any resources used by the object. [...]
override
getKindForPointer(int pointer) PointerDeviceKind
For a given pointer ID, returns the device kind associated with it. [...]
@protected, inherited
handleNonAllowedPointer(PointerDownEvent event) → void
Handles a pointer being added that's not allowed by this recognizer. [...]
@protected, inherited
invokeCallback<T>(String name, RecognizerCallback<T> callback, {String debugReport()}) → T?
Invoke a callback provided by the application, catching and logging any exceptions. [...]
@protected, inherited
isPointerAllowed(PointerDownEvent event) bool
Checks whether or not a pointer is allowed to be tracked by this recognizer.
@protected, inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
rejectGesture(int pointer) → void
Called when this member loses the arena for the given pointer id.
override
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
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 brief description of this object, usually just the runtimeType and the hashCode. [...]
inherited

Operators

operator ==(Object other) bool
The equality operator. [...]
inherited