TapGestureRecognizer class Null safety
Recognizes taps.
Gesture recognizers take part in gesture arenas to enable potential gestures to be disambiguated from each other. This process is managed by a GestureArenaManager.
TapGestureRecognizer considers all the pointers involved in the pointer event sequence as contributing to one gesture. For this reason, extra pointer interactions during a tap sequence are not recognized as additional taps. For example, down-1, down-2, up-1, up-2 produces only one tap on up-1.
TapGestureRecognizer competes on pointer events of kPrimaryButton only
when it has at least one non-null onTap* callback, on events of
kSecondaryButton only when it has at least one non-null onSecondaryTap*
callback, and on events of kTertiaryButton only when it has at least
one non-null onTertiaryTap* callback. If it has no callbacks, it is a
no-op.
See also:
- GestureDetector.onTap, which uses this recognizer.
- MultiTapGestureRecognizer
- Inheritance
Constructors
-
TapGestureRecognizer({Object? debugOwner, Set<
PointerDeviceKind> ? supportedDevices}) - Creates a tap gesture recognizer. [...]
Properties
- deadline → Duration?
-
If non-null, the recognizer will call didExceedDeadline after this
amount of time has elapsed since starting to track the primary pointer. [...]
final, inherited
- debugDescription → String
-
Returns a very short pretty description of the gesture that the
recognizer looks for, like 'tap' or 'horizontal drag'.
read-only, override
- debugOwner → Object?
-
The recognizer's owner. [...]
final, inherited
- gestureSettings ↔ DeviceGestureSettings?
-
Optional device specific configuration for device gestures that will
take precedence over framework defaults.
read / write, inherited
- hashCode → int
-
The hash code for this object. [...]
read-only, inherited
- initialPosition → OffsetPair?
-
The location at which the primary pointer contacted the screen. [...]
read-only, inherited
- onSecondaryTap ↔ GestureTapCallback?
-
A pointer has stopped contacting the screen, which is recognized as a tap
of a secondary button. [...]
read / write
- onSecondaryTapCancel ↔ GestureTapCancelCallback?
-
A pointer that previously triggered onSecondaryTapDown will not end up
causing a tap. [...]
read / write
- onSecondaryTapDown ↔ GestureTapDownCallback?
-
A pointer has contacted the screen at a particular location with a
secondary button, which might be the start of a secondary tap. [...]
read / write
- onSecondaryTapUp ↔ GestureTapUpCallback?
-
A pointer has stopped contacting the screen at a particular location,
which is recognized as a tap of a secondary button. [...]
read / write
- onTap ↔ GestureTapCallback?
-
A pointer has stopped contacting the screen, which is recognized as a tap
of a primary button. [...]
read / write
- onTapCancel ↔ GestureTapCancelCallback?
-
A pointer that previously triggered onTapDown will not end up causing
a tap. [...]
read / write
- onTapDown ↔ GestureTapDownCallback?
-
A pointer has contacted the screen at a particular location with a primary
button, which might be the start of a tap. [...]
read / write
- onTapUp ↔ GestureTapUpCallback?
-
A pointer has stopped contacting the screen at a particular location,
which is recognized as a tap of a primary button. [...]
read / write
- onTertiaryTapCancel ↔ GestureTapCancelCallback?
-
A pointer that previously triggered onTertiaryTapDown will not end up
causing a tap. [...]
read / write
- onTertiaryTapDown ↔ GestureTapDownCallback?
-
A pointer has contacted the screen at a particular location with a
tertiary button, which might be the start of a tertiary tap. [...]
read / write
- onTertiaryTapUp ↔ GestureTapUpCallback?
-
A pointer has stopped contacting the screen at a particular location,
which is recognized as a tap of a tertiary button. [...]
read / write
- postAcceptSlopTolerance → double?
-
The maximum distance in logical pixels the gesture is allowed to drift
after the gesture has been accepted. [...]
final, inherited
- preAcceptSlopTolerance → double?
-
The maximum distance in logical pixels the gesture is allowed to drift
from the initial touch down position before the gesture is accepted. [...]
final, inherited
- primaryPointer → int?
-
The ID of the primary pointer this recognizer is tracking. [...]
read-only, inherited
- runtimeType → Type
-
A representation of the runtime type of the object.
read-only, inherited
- state → GestureRecognizerState
-
The current state of the recognizer. [...]
read-only, inherited
- team ↔ GestureArenaTeam?
-
The team that this recognizer belongs to, if any. [...]
read / write, inherited
Methods
-
acceptGesture(
int pointer) → void -
Called when this member wins the arena for the given pointer id.
inherited
-
addAllowedPointer(
PointerDownEvent event) → void -
Registers a new pointer that's been checked to be allowed by this gesture
recognizer. [...]
inherited
-
addPointer(
PointerDownEvent event) → void -
Registers a new pointer that might be relevant to this gesture
detector. [...]
inherited
-
debugDescribeChildren(
) → List< DiagnosticsNode> -
Returns a list of
DiagnosticsNodeobjects describing this node's children. [...]inherited -
debugFillProperties(
DiagnosticPropertiesBuilder properties) → void -
Add additional properties associated with the node. [...]
inherited
-
didExceedDeadline(
) → void -
Override to be notified when deadline is exceeded. [...]
inherited
-
didExceedDeadlineWithEvent(
PointerDownEvent event) → void -
Same as didExceedDeadline but receives the
eventthat initiated the gesture. [...]@protected, inherited -
didStopTrackingLastPointer(
int pointer) → void -
Called when the number of pointers this recognizer is tracking changes from one to zero. [...]
inherited
-
dispose(
) → void -
Releases any resources used by the object. [...]
inherited
-
getKindForPointer(
int pointer) → PointerDeviceKind -
For a given pointer ID, returns the device kind associated with it. [...]
@protected, inherited
-
handleEvent(
PointerEvent event) → void -
Called when a pointer event is routed to this recognizer. [...]
inherited
-
handleNonAllowedPointer(
PointerDownEvent event) → void -
Handles a pointer being added that's not allowed by this recognizer. [...]
inherited
-
handlePrimaryPointer(
PointerEvent event) → void -
Override to provide behavior for the primary pointer when the gesture is still possible.
inherited
-
handleTapCancel(
{required PointerDownEvent down, PointerCancelEvent? cancel, required String reason}) → void -
A pointer that previously triggered handleTapDown will not end up
causing a tap. [...]
@protected, override
-
handleTapDown(
{required PointerDownEvent down}) → void -
A pointer has contacted the screen, which might be the start of a tap. [...]
@protected, override
-
handleTapUp(
{required PointerDownEvent down, required PointerUpEvent up}) → void -
A pointer has stopped contacting the screen, which is recognized as a tap. [...]
@protected, override
-
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.
override
-
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
-
resolvePointer(
int pointer, GestureDisposition disposition) → void -
Resolves this recognizer's participation in the given gesture arena with
the given disposition.
@mustCallSuper, @protected, inherited
-
startTrackingPointer(
int pointer, [Matrix4? transform]) → void -
Causes events related to the given pointer ID to be routed to this recognizer. [...]
@protected, inherited
-
stopTrackingIfPointerNoLongerDown(
PointerEvent event) → void -
Stops tracking the pointer associated with the given event if the event is
a PointerUpEvent or a PointerCancelEvent event.
@protected, inherited
-
stopTrackingPointer(
int pointer) → void -
Stops events related to the given pointer ID from being routed to this recognizer. [...]
@protected, 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 brief description of this object, usually just the runtimeType and the
hashCode. [...]
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator. [...]
inherited