| Inherits from | UIEvent |
| Availability | Available in iPhone OS 2.0 and later. |
| Companion guide |
The TouchEvent class encapsulates information about a touch event.
The system continually sends TouchEvent objects to an application as fingers touch and move across a surface. A touch event provides a snapshot of all touches during a multi-touch sequence, most importantly the touches that are new or have changed for a particular target. A multi-touch sequence begins when a finger first touches the surface. Other fingers may subsequently touch the surface, and all fingers may move across the surface. The sequence ends when the last of these fingers is lifted from the surface. An application receives touch event objects during each phase of any touch.
The different types of TouchEvent objects that can occur are:
touchstartSent when a finger for a given event touches the surface.
touchmoveSent when a given event moves on the surface.
touchendSent when a given event lifts from the surface.
touchcancelSent when the system cancels tracking for the touch.
TouchEvent objects are combined together to form high-level GestureEvent objects that are also sent during a multi-touch sequence. See GestureEvent for details on GestureEvent objects and an example of the events sent for a two finger multi-touch gesture.
If true, the alt key is pressed; otherwise, it is not. If there is no keyboard, this value is false.
readonly attribute boolean altKey;
A collection of Touch objects representing all touches that changed in this event.
readonly attribute TouchList changedTouches;
You manipulate this collection using TouchList methods.
Initializes a newly created TouchEvent object.
void initTouchEvent( in DOMString type, in boolean canBubble, in boolean cancelable, in DOMWindow view, in long detail, in long screenX, in long screenY, in long clientX, in long clientY, in boolean ctrlKey, in boolean altKey, in boolean shiftKey, in boolean metaKey, in TouchList touches, in TouchList targetTouches, in TouchList changedTouches, in float scale, in float rotation);
The type of event that occurred.
Indicates whether an event can bubble. If true, the event can bubble; otherwise, it cannot.
Indicates whether an event can have its default action prevented. If true, the default action can be prevented; otherwise, it cannot.
The view (DOM window) in which the event occurred.
Specifies some detail information about the event depending on the type of event.
The x-coordinate of the event’s location in screen coordinates.
The y-coordinate of the event’s location in screen coordinates.
The x-coordinate of the event’s location relative to the window’s viewport.
The y-coordinate of the event’s location relative to the window’s viewport.
If true, the control key is pressed; otherwise, it is not.
If true, the alt key is pressed; otherwise, it is not.
If true, the shift key is pressed; otherwise, it is not.
If true, the meta key is pressed; otherwise, it is not.
A collection of Touch objects representing all touches associated with this event.
A collection of Touch objects representing all touches associated with this target.
A collection of Touch objects representing all touches that changed in this event.
The distance between two fingers since the start of an event as a multiplier of the initial distance. The initial value is 1.0. If less than 1.0, the gesture is pinch close (to zoom out). If greater than 1.0, the gesture is pinch open (to zoom in).
The delta rotation since the start of an event, in degrees, where clockwise is positive and counter-clockwise is negative. The initial value is 0.0.
Use this method to programmatically create a TouchEvent object.
Last updated: 2010-02-24