Recognizes a scale gesture.
ScaleGestureRecognizer tracks the pointers in contact with the screen and calculates their focal point and indiciated scale. When a focal pointer is established, the recognizer calls onStart. As the focal point and scale change, the recognizer calls onUpdate. When the pointers are no longer in contact with the screen, the recognizer calls onEnd.
- Inheritance
- Object
- GestureArenaMember
- GestureRecognizer
- OneSequenceGestureRecognizer
- ScaleGestureRecognizer
Constructors
Properties
- onEnd → GestureScaleEndCallback
-
The pointers are no longer in contact with the screen.
read / write - onStart → GestureScaleStartCallback
-
The pointers in contact with the screen have established a focal point and initial scale of 1.0.
read / write - onUpdate → GestureScaleUpdateCallback
-
The pointers in contact with the screen have indicated a new focal point and/or scale.
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.
-
toStringShort(
) → String -
Returns a very short pretty description of the gesture that the recognizer looks for, like 'tap' or 'horizontal drag'.
-
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 -
rejectGesture(
int pointer) → void -
Called when this member loses the arena for the given pointer id.
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