Touch extension type
The Touch
interface represents a single contact point on a
touch-sensitive device. The contact point is commonly a finger or stylus and
the device may be a touchscreen or trackpad.
The Touch.radiusX, Touch.radiusY, and Touch.rotationAngle describe the area of contact between the user and the screen, the touch area. This can be helpful when dealing with imprecise pointing devices such as fingers. These values are set to describe an ellipse that as closely as possible matches the entire area of contact (such as the user's fingertip).
Note: Many of the properties' values are hardware-dependent; for example, if the device doesn't have a way to detect the amount of pressure placed on the surface, the
force
value will always be 0. This may also be the case forradiusX
andradiusY
; if the hardware reports only a single point, these values will be 1.
API documentation sourced from MDN Web Docs.
- on
- Implemented types
- Available extensions
Properties
- altitudeAngle → double
-
no setter
- azimuthAngle → double
-
no setter
-
client
→ Point<
num> -
Available on Touch, provided by the TouchGlue extension
A Point representation of the clientX and clientY properties of this Touch event.no setter - clientX → double
-
The
Touch.clientX
read-only property returns the X coordinate of the touch point relative to the viewport, not including any scroll offset.no setter - clientY → double
-
The
Touch.clientY
read-only property returns the Y coordinate of the touch point relative to the browser's viewport, not including any scroll offset.no setter - force → double
-
The
Touch.force
read-only property returns the amount of pressure the user is applying to the touch surface for a Touch point.no setter - hashCode → int
-
The hash code for this object.
no setterinherited
- identifier → int
-
The
Touch.identifier
returns a value uniquely identifying this point of contact with the touch surface. This value remains consistent for every event involving this finger's (or stylus's) movement on the surface until it is lifted off the surface.no setter - isDefinedAndNotNull → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
no setter - isNull → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
Whether this value corresponds to JavaScriptnull
.no setter - isTruthy → JSBoolean
-
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of!!
in JavaScript.this
no setter - isUndefined → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
Whether this value corresponds to JavaScriptundefined
.no setter - isUndefinedOrNull → bool
-
Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension
no setter - not → JSBoolean
-
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of!
in JavaScript.this
no setter - pageX → double
-
The
Touch.pageX
read-only property returns the X coordinate of the touch point relative to the viewport, including any scroll offset.no setter - pageY → double
-
The
Touch.pageY
read-only property returns the Y coordinate of the touch point relative to the viewport, including any scroll offset.no setter - radiusX → double
-
The
radiusX
read-only property of the Touch interface returns the X radius of the ellipse that most closely circumscribes the area of contact with the touch surface. The value is in CSS pixels of the same scale as Touch.screenX.no setter - radiusY → double
-
The
radiusY
read-only property of the Touch interface returns the Y radius of the ellipse that most closely circumscribes the area of contact with the touch surface. The value is in CSS pixels of the same scale as Touch.screenX.no setter - rotationAngle → double
-
The
rotationAngle
read-only property of the Touch interface returns the rotation angle, in degrees, of the contact area ellipse defined by Touch.radiusX and Touch.radiusY. The value may be between 0 and 90. Together, these three values describe an ellipse that approximates the size and shape of the area of contact between the user and the screen. This may be a relatively large ellipse representing the contact between a fingertip and the screen or a small area representing the tip of a stylus, for example.no setter - runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- screenX → double
-
Returns the X coordinate of the touch point relative to the screen, not
including any scroll offset.
no setter
- screenY → double
-
Returns the Y coordinate of the touch point relative to the screen, not
including any scroll offset.
no setter
- target → EventTarget
-
The read-only
target
property of theTouch
interface returns the (EventTarget) on which the touch contact started when it was first placed on the surface, even if the touch point has since moved outside the interactive area of that element or even been removed from the document. Note that if the target element is removed from the document, events will still be targeted at it, and hence won't necessarily bubble up to the window or document anymore. If there is any risk of an element being removed while it is being touched, the best practice is to attach the touch listeners directly to the target.no setter - touchType → TouchType
-
no setter
Methods
-
add(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
+any
-
and(
JSAny? any) → JSAny? -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
&&any
-
callMethod<
R extends JSAny?> (JSAny method, [JSAny? arg1, JSAny? arg2, JSAny? arg3, JSAny? arg4]) → R -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Callsmethod
on this JSObject with up to four arguments. -
callMethodVarArgs<
R extends JSAny?> (JSAny method, [List< JSAny?> ? arguments]) → R -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Callsmethod
on this JSObject with a variable number ofarguments
. -
dartify(
) → Object? -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Converts a JavaScript value to the Dart equivalent if possible. -
delete(
JSAny property) → JSBoolean -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Deletes the property with keyproperty
from this JSObject. -
divide(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
/any
-
equals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
==any
-
exponentiate(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
**any
-
getProperty<
R extends JSAny?> (JSAny property) → R -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
The value of the property keyproperty
of this JSObject. -
greaterThan(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
>any
-
greaterThanOrEqualTo(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
>=any
-
has(
String property) → bool -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Shorthand helper for hasProperty to check whether this JSObject contains the property keyproperty
, but takes and returns a Dart value. -
hasProperty(
JSAny property) → JSBoolean -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Whether or not this JSObject contains the property keyproperty
. -
instanceof(
JSFunction constructor) → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether thisJSAny?
is aninstanceof
constructor
. -
instanceOfString(
String constructorName) → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether thisJSAny?
is aninstanceof
the constructor that is defined byconstructorName
, which is looked up in the globalContext. -
isA<
T extends JSAny?> () → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether thisJSAny?
is an instance of the JavaScript type that is declared byT
. -
lessThan(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
<any
-
lessThanOrEqualTo(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
<=any
-
modulo(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
%any
-
multiply(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
*any
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a nonexistent method or property is accessed.
inherited
-
notEquals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
!=any
-
or(
JSAny? any) → JSAny? -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
||any
-
setProperty(
JSAny property, JSAny? value) → void -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Write thevalue
of property keyproperty
of this JSObject. -
strictEquals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
===any
-
strictNotEquals(
JSAny? any) → JSBoolean -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
!==any
-
subtract(
JSAny? any) → JSAny -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
-any
-
toString(
) → String -
A string representation of this object.
inherited
-
typeofEquals(
String typeString) → bool -
Available on JSAny?, provided by the JSAnyUtilityExtension extension
Whether the result oftypeof
on thisJSAny?
istypeString
. -
unsignedRightShift(
JSAny? any) → JSNumber -
Available on JSAny?, provided by the JSAnyOperatorExtension extension
The result of
in JavaScript.this
>>>any
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited
-
operator [](
String property) → JSAny? -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Shorthand helper for getProperty to get the value of the property keyproperty
of this JSObject, but takes and returns a Dart value. -
operator []=(
String property, JSAny? value) → void -
Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension
Shorthand helper for setProperty to write thevalue
of the property keyproperty
of this JSObject, but takes a Dart value.