Recognizes movement.

In contrast to MultiDragGestureRecognizer, DragGestureRecognizer recognizes a single gesture sequence for all the pointers it watches, which means that the recognizer has at most one drag sequence active at any given time regardless of how many pointers are in contact with the screen.

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

See also:

Inheritance
Implemented by

Constructors

DragGestureRecognizer()

Properties

onCancel GestureDragCancelCallback

The pointer that previously triggered onDown did not complete.

read / write
onDown GestureDragDownCallback

A pointer has contacted the screen and might begin to move.

read / write
onEnd GestureDragEndCallback

A pointer that was previously in contact with the screen and moving is no longer in contact with the screen and was moving at a specific velocity when it stopped contacting the screen.

read / write
onStart GestureDragStartCallback

A pointer has contacted the screen and has begun to move.

read / write
onUpdate GestureDragUpdateCallback

A pointer that is in contact with the screen and moving has moved again.

read / write
hashCode int

Get a hash code for this object.

read-only, inherited
runtimeType Type

A representation of the runtime type of the object.

read-only, inherited

Operators

operator ==(other) bool

The equality operator.

inherited

Methods

acceptGesture(int pointer) → void

Called when this member wins the arena for the given pointer id.

addPointer(PointerEvent event) → void

Registers a new pointer that might be relevant to this gesture detector.

didStopTrackingLastPointer(int pointer) → void

Called when the number of pointers this recognizer is tracking changes from one to zero.

dispose() → void

Releases any resources used by the object.

handleEvent(PointerEvent event) → void

Called when a pointer event is routed to this recognizer.

rejectGesture(int pointer) → void

Called when this member loses the arena for the given pointer id.

invokeCallback(String name, RecognizerCallback callback) → dynamic

Invoke a callback provided by the application and log any exceptions.

inherited
noSuchMethod(Invocation invocation) → dynamic

Invoked when a non-existent method or property is accessed.

inherited
resolve(GestureDisposition disposition) → void

Resolves this recognizer's participation in each gesture arena with the given disposition.

inherited
startTrackingPointer(int pointer) → void

Causes events related to the given pointer ID to be routed to this recognizer.

inherited
stopTrackingIfPointerNoLongerDown(PointerEvent event) → void

Stops tracking the pointer associated with the given event if the event is a PointerUpEvent or a PointerCancelEvent event.

inherited
stopTrackingPointer(int pointer) → void

Stops events related to the given pointer ID from being routed to this recognizer.

inherited
toString() String

Returns a string representation of this object.

inherited
toStringShort() String

Returns a very short pretty description of the gesture that the recognizer looks for, like 'tap' or 'horizontal drag'.

inherited