gestures library

The Flutter gesture recognizers.

To use, import package:flutter/gestures.dart.

Classes

DelayedMultiDragGestureRecognizer
Recognizes movement both horizontally and vertically on a per-pointer basis after a delay. [...]
DoubleTapGestureRecognizer
Recognizes when the user has tapped the screen at the same location twice in quick succession.
Drag
Interface for objects that receive updates about drags. [...]
DragDownDetails
Details object for callbacks that use GestureDragDownCallback. [...]
DragEndDetails
Details object for callbacks that use GestureDragEndCallback. [...]
DragGestureRecognizer
Recognizes movement. [...]
DragStartDetails
Details object for callbacks that use GestureDragStartCallback. [...]
DragUpdateDetails
Details object for callbacks that use GestureDragUpdateCallback. [...]
FlutterErrorDetailsForPointerEventDispatcher
Variant of FlutterErrorDetails with extra fields for the gesture library's binding's pointer event dispatcher (GestureBinding.dispatchEvent). [...]
FlutterErrorDetailsForPointerRouter
Variant of FlutterErrorDetails with extra fields for the gestures library's pointer router (PointerRouter). [...]
GestureArenaEntry
An interface to information to an arena. [...]
GestureArenaManager
The first member to accept or the last member to not reject wins. [...]
GestureArenaMember
Represents an object participating in an arena. [...]
GestureArenaTeam
A group of GestureArenaMember objects that are competing as a unit in the GestureArenaManager. [...]
GestureBinding
A binding for the gesture subsystem.
GestureRecognizer
The base class that all gesture recognizers inherit from. [...]
HitTestable
An object that can hit-test pointers.
HitTestDispatcher
An object that can dispatch events.
HitTestEntry
Data collected during a hit test about a specific HitTestTarget. [...]
HitTestResult
The result of performing a hit test.
HitTestTarget
An object that can handle events.
HorizontalDragGestureRecognizer
Recognizes movement in the horizontal direction. [...]
HorizontalMultiDragGestureRecognizer
Recognizes movement in the horizontal direction on a per-pointer basis. [...]
ImmediateMultiDragGestureRecognizer
Recognizes movement both horizontally and vertically on a per-pointer basis. [...]
LeastSquaresSolver
Uses the least-squares algorithm to fit a polynomial to a set of data.
LongPressGestureRecognizer
Recognizes when the user has pressed down at the same location for a long period of time.
MultiDragGestureRecognizer<T extends MultiDragPointerState>
Recognizes movement on a per-pointer basis. [...]
MultiDragPointerState
Per-pointer state for a MultiDragGestureRecognizer. [...]
MultiTapGestureRecognizer
Recognizes taps on a per-pointer basis. [...]
Offset
An immutable 2D floating-point offset. [...]
OneSequenceGestureRecognizer
Base class for gesture recognizers that can only recognize one gesture at a time. For example, a single TapGestureRecognizer can never recognize two taps happening simultaneously, even if multiple pointers are placed on the same widget. [...]
PanGestureRecognizer
Recognizes movement both horizontally and vertically. [...]
PointerAddedEvent
The device has started tracking the pointer. [...]
PointerCancelEvent
The input from the pointer is no longer directed towards this receiver.
PointerDownEvent
The pointer has made contact with the device.
PointerEvent
Base class for touch, stylus, or mouse events. [...]
PointerEventConverter
Converts from engine pointer data to framework pointer events. [...]
PointerHoverEvent
The pointer has moved with respect to the device while the pointer is not in contact with the device. [...]
PointerMoveEvent
The pointer has moved with respect to the device while the pointer is in contact with the device. [...]
PointerRemovedEvent
The device is no longer tracking the pointer. [...]
PointerRouter
A routing table for PointerEvent events.
PointerUpEvent
The pointer has stopped making contact with the device.
PolynomialFit
An nth degree polynomial fit to a dataset.
PrimaryPointerGestureRecognizer
A base class for gesture recognizers that track a single primary pointer. [...]
ScaleEndDetails
Details for GestureScaleEndCallback.
ScaleGestureRecognizer
Recognizes a scale gesture. [...]
ScaleStartDetails
Details for GestureScaleStartCallback.
ScaleUpdateDetails
Details for GestureScaleUpdateCallback.
TapDownDetails
Details for GestureTapDownCallback, such as position. [...]
TapGestureRecognizer
Recognizes taps. [...]
TapUpDetails
Details for GestureTapUpCallback, such as position. [...]
Velocity
A velocity in two dimensions.
VelocityEstimate
A two dimensional velocity estimate. [...]
VelocityTracker
Computes a pointer's velocity based on data from PointerMoveEvents. [...]
VerticalDragGestureRecognizer
Recognizes movement in the vertical direction. [...]
VerticalMultiDragGestureRecognizer
Recognizes movement in the vertical direction on a per-pointer basis. [...]

Constants

kBackMouseButton → const int
The bit of PointerEvent.buttons that corresponds to the back mouse button. [...]
0x08
kDoubleTapMinTime → const Duration
The minimum time from the end of the first tap to the start of the second tap in a double-tap gesture. (Currently not honored by the DoubleTapGestureRecognizer.)
const Duration(milliseconds: 40)
kDoubleTapSlop → const double
Distance between the initial position of the first touch and the start position of a potential second touch for the second touch to be considered the second touch of a double-tap gesture.
100.0
kDoubleTapTimeout → const Duration
The maximum time from the start of the first tap to the start of the second tap in a double-tap gesture.
const Duration(milliseconds: 300)
kDoubleTapTouchSlop → const double
The maximum distance that the first touch in a double-tap gesture can travel before deciding that it is not part of a double-tap gesture. DoubleTapGestureRecognizer also restricts the second touch to this distance.
kTouchSlop
kForwardMouseButton → const int
The bit of PointerEvent.buttons that corresponds to the forward mouse button. [...]
0x10
kHoverTapSlop → const double
Maximum distance between the down and up pointers for a tap. (Currently not honored by the TapGestureRecognizer; PrimaryPointerGestureRecognizer, which TapGestureRecognizer inherits from, uses kTouchSlop.)
20.0
kHoverTapTimeout → const Duration
Maximum length of time between a tap down and a tap up for the gesture to be considered a tap. (Currently not honored by the TapGestureRecognizer.)
const Duration(milliseconds: 150)
kJumpTapTimeout → const Duration
The maximum time from the start of the first tap to the start of the second tap in a jump-tap gesture.
const Duration(milliseconds: 500)
kLongPressTimeout → const Duration
The time before a long press gesture attempts to win.
const Duration(milliseconds: 500)
kMaxFlingVelocity → const double
Drag gesture fling velocities are clipped to this value.
8000.0
kMiddleMouseButton → const int
The bit of PointerEvent.buttons that corresponds to the middle mouse button. [...]
0x04
kMinFlingVelocity → const double
The minimum velocity for a touch to consider that touch to trigger a fling gesture.
50.0
kPagingTouchSlop → const double
The distance a touch has to travel for the framework to be confident that the gesture is a paging gesture. (Currently not used, because paging uses a regular drag gesture, which uses kTouchSlop.)
kTouchSlop * 2.0
kPanSlop → const double
The distance a touch has to travel for the framework to be confident that the gesture is a panning gesture.
kTouchSlop * 2.0
kPressTimeout → const Duration
The time that must elapse before a tap gesture sends onTapDown, if there's any doubt that the gesture is a tap.
const Duration(milliseconds: 100)
kPrimaryMouseButton → const int
The bit of PointerEvent.buttons that corresponds to the primary mouse button. [...]
0x01
kPrimaryStylusButton → const int
The bit of PointerEvent.buttons that corresponds to the primary stylus button. [...]
0x02
kScaleSlop → const double
The distance a touch has to travel for the framework to be confident that the gesture is a scale gesture.
kTouchSlop
kSecondaryMouseButton → const int
The bit of PointerEvent.buttons that corresponds to the secondary mouse button. [...]
0x02
kSecondaryStylusButton → const int
The bit of PointerEvent.buttons that corresponds to the secondary stylus button. [...]
0x04
kTouchSlop → const double
The distance a touch has to travel for the framework to be confident that the gesture is a scroll gesture, or, inversely, the maximum distance that a touch can travel before the framework becomes confident that it is not a tap.
18.0
kWindowTouchSlop → const double
The margin around a dialog, popup menu, or other window-like widget inside which we do not consider a tap to dismiss the widget. (Not currently used.)
16.0
kZoomControlsTimeout → const Duration
The time for which zoom controls (e.g. in a map interface) are to be displayed on the screen, from the moment they were last requested.
const Duration(milliseconds: 3000)

Properties

debugPrintGestureArenaDiagnostics bool
Prints information about gesture recognizers and gesture arenas. [...]
read / write
debugPrintHitTestResults bool
Whether to print the results of each hit test to the console. [...]
read / write
debugPrintRecognizerCallbacksTrace bool
Logs a message every time a gesture recognizer callback is invoked. [...]
read / write

Functions

debugAssertAllGesturesVarsUnset(String reason) bool
Returns true if none of the gestures library debug variables have been changed. [...]
nthMouseButton(int number) int
The bit of PointerEvent.buttons that corresponds to the nth mouse button. [...]
nthStylusButton(int number) int
The bit of PointerEvent.buttons that corresponds to the nth stylus button. [...]

Enums

GestureDisposition
Whether the gesture was accepted or rejected.
GestureRecognizerState
The possible states of a PrimaryPointerGestureRecognizer. [...]
PointerDeviceKind
The kind of pointer device.

Typedefs

GestureDoubleTapCallback() → void
Signature for callback when the user has tapped the screen at the same location twice in quick succession.
GestureDragCancelCallback() → void
Signature for when the pointer that previously triggered a GestureDragDownCallback did not complete. [...]
GestureDragDownCallback(DragDownDetails details) → void
Signature for when a pointer has contacted the screen and might begin to move. [...]
GestureDragEndCallback(DragEndDetails details) → void
Signature for when a pointer that was previously in contact with the screen and moving is no longer in contact with the screen. [...]
GestureDragStartCallback(DragStartDetails details) → void
Signature for when a pointer has contacted the screen and has begun to move. [...]
GestureDragUpdateCallback(DragUpdateDetails details) → void
Signature for when a pointer that is in contact with the screen and moving has moved again. [...]
GestureLongPressCallback() → void
Signature for when a pointer has remained in contact with the screen at the same location for a long period of time.
GestureMultiDragStartCallback(Offset position) Drag
Signature for when MultiDragGestureRecognizer recognizes the start of a drag gesture.
GestureMultiTapCallback(int pointer) → void
Signature used by MultiTapGestureRecognizer for when a tap has occurred.
GestureMultiTapCancelCallback(int pointer) → void
Signature for when the pointer that previously triggered a GestureMultiTapDownCallback will not end up causing a tap.
GestureMultiTapDownCallback(int pointer, TapDownDetails details) → void
Signature used by MultiTapGestureRecognizer for when a pointer that might cause a tap has contacted the screen at a particular location.
GestureMultiTapUpCallback(int pointer, TapUpDetails details) → void
Signature used by MultiTapGestureRecognizer for when a pointer that will trigger a tap has stopped contacting the screen at a particular location.
GestureScaleEndCallback(ScaleEndDetails details) → void
Signature for when the pointers are no longer in contact with the screen.
GestureScaleStartCallback(ScaleStartDetails details) → void
Signature for when the pointers in contact with the screen have established a focal point and initial scale of 1.0.
GestureScaleUpdateCallback(ScaleUpdateDetails details) → void
Signature for when the pointers in contact with the screen have indicated a new focal point and/or scale.
GestureTapCallback() → void
Signature for when a tap has occurred. [...]
GestureTapCancelCallback() → void
Signature for when the pointer that previously triggered a GestureTapDownCallback will not end up causing a tap. [...]
GestureTapDownCallback(TapDownDetails details) → void
Signature for when a pointer that might cause a tap has contacted the screen. [...]
GestureTapUpCallback(TapUpDetails details) → void
Signature for when a pointer that will trigger a tap has stopped contacting the screen. [...]
PointerRoute(PointerEvent event) → void
A callback that receives a PointerEvent
RecognizerCallback<T>() → T
Generic signature for callbacks passed to GestureRecognizer.invokeCallback. This allows the GestureRecognizer.invokeCallback mechanism to be generically used with anonymous functions that return objects of particular types.