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A pointer is a hardware agnostic representation of input devices (such as a mouse, pen or contact point on a touch-enable surface). The pointer can target a specific coordinate (or set of coordinates) on the contact surface such as a screen.
A pointer's hit test is the process a browser uses to determine the target element for a pointer event. Typically, this is determined by considering the pointer's location and also the visual layout of elements in a document on screen media.
The PointerEvent
interface represents the state of a DOM event produced by a pointer such as the geometry of the contact point, the device type that generated the event, the amount of pressure that was applied on the contact surface, etc.
Properties
This interface inherits properties from MouseEvent
and Event
.
PointerEvent.pointerId
Read only- A unique identifier for the pointer causing the event.
PointerEvent.width
Read only- The width (magnitude on the X axis), in CSS pixels, of the contact geometry of the pointer.
PointerEvent.height
Read only- The height (magnitude on the Y axis), in CSS pixels, of the contact geometry of the pointer.
PointerEvent.pressure
Read only- The normalized pressure of the pointer input in the range of 0 to 1, where 0 and 1 represent the minimum and maximum pressure the hardware is capable of detecting, respectively.
PointerEvent.tiltX
Read only- The plane angle (in degrees, in the range of -90 to 90) between the Y-Z plane and the plane containing both the transducer (e.g. pen stylus) axis and the Y axis.
PointerEvent.tiltY
Read only- The plane angle (in degrees, in the range of -90 to 90) between the X-Z plane and the plane containing both the transducer (e.g. pen stylus) axis and the X axis.
PointerEvent.pointerType
Read only- Indicates the device type that caused the event (mouse, pen, touch, etc.)
PointerEvent.isPrimary
Read only- Indicates if the pointer represents the primary pointer of this pointer type.
Constructors
PointerEvent()
- Creates a synthetic and untrusted PointerEvent.
Pointer event types
The PointerEvent
interface has several event types. To determine which event fired, look at the event's type
property.
event.preventDefault()
to keep the mouse event from being sent as well.pointerover
- This event is fired when a pointing device is moved into an element's hit test boundaries.
pointerenter
- This event is fired when when a pointing device is moved into the hit test boundaries of an element or one of its descendants, including as a result of a pointerdown event from a device that does not support hover (see pointerdown). This event type is similar to pointerover, but differs in that it does not bubble.
pointerdown
- The event is fired when a pointer becomes active. For mouse, it is fired when the device transitions from no buttons depressed to at least one button depressed. For touch, it is fired when physical contact is made with the digitizer. For pen, it is fired when the stylus makes physical contact with the digitizer.
pointermove
- This event is fired when a pointer changes coordinates.
pointerup
- This event is fired when a pointer is no longer active.
pointercancel
- A browser fires this event if it concludes the pointer will no longer be able to generate events (for example the related device is deactived).
pointerout
- This event is fired for several reasons including: pointing device is moved out of the hit test boundaries of an element; firing the pointerup event for a device that does not support hover (see pointerup); after firing the pointercancel event (see pointercancel); when a pen stylus leaves the hover range detectable by the digitizer.
pointerleave
- This event is fired when a pointing device is moved out of the hit test boundaries of an element. For pen devices, this event is fired when the stylus leaves the hover range detectable by the digitizer.
gotpointercapture
- This event is fired when an element receives pointer capture.
lostpointercapture
- This event is fired after pointer capture is released for a pointer.
GlobalEventHandlers
GlobalEventHandlers.onpointerover
- A
global event handler
for thepointerover
event. GlobalEventHandlers.onpointerenter
- A
global event handler
for thepointerenter
event. GlobalEventHandlers.onpointerdown
- A
global event handler
for thepointerdown
event. GlobalEventHandlers.onpointermove
- A
global event handler
for thepointermove
event. GlobalEventHandlers.onpointerup
- A
global event handler
for thepointerup
event. GlobalEventHandlers.onpointercancel
- A
global event handler
for thepointercancel
event. GlobalEventHandlers.onpointerout
- A
global event handler
for thepointerout
event. GlobalEventHandlers.onpointerleave
- A
global event handler
for thepointerleave
event.
Example
An Example of each property, event type and global event handler is included in their respective reference page.
Specifications
Specification | Status | Comment |
---|---|---|
Pointer Events – Level 2 The definition of 'PointerEvent' in that specification. |
Editor's Draft | Non-stable version. |
Pointer Events The definition of 'PointerEvent' in that specification. |
Recommendation | Initial definition. |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | No support[2] | No support [1] | 10ms 11 |
No support | No support |
touch-action property |
No support | No support [3] | 11 | No support | No support |
Feature | Android | Android Webview | Chrome for Android | Firefox Mobile (Gecko) | Firefox OS | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|---|
Basic support | No support | No support | No support | No support [1] | No support | 10 | No support | No support |
touch-action property |
No support | No support | No support | No support [3] | No support | No support | No support |
[1] This feature is currently hidden behind a flag; to enable it and experiment, set the dom.w3c_pointer_events.enabled
preference to true
in about:config
.
[2] In development, see: crbug.com/196799.
[3] Starting in Firefox 29, touch-action
is implemented in Firefox, but is hidden behind the layout.css.touch_action.enabled
preference. Starting in Firefox Nighly 50, it is enabled by default when running in nightly builds only; no decision has been made on when it will make its way along toward release. You still need to separately enable the dom.w3c_pointer_events.enabled
preference, however.