Event

Event handlers subscribed via EventManager.on() will be called with one parameter. This event parameter always has the following properties:

• type (string) - The event type to which the event handler is subscribed, e.g. 'click' or 'pointermove'
• center (Object {x, y}) - The center of the event location (e.g. the centroid of a touch) relative to the viewport (basically, clientX/Y)
• offsetCenter (Object {x, y}) - The center of the event location (e.g. the centroid of a touch)
• target (Object) - The target of the event, as specified by the original srcEvent
• srcEvent (Object) - The original event object dispatched by the browser to the JS runtime
• preventDefault (Function) - Equivalent to srcEvent.preventDefault.
• stopPropagation (Function) - Do not invoke handlers registered for any ancestors in the DOM tree.
• stopImmediatePropagation (Function) - Do not invoke any other handlers registered for the same element or its ancestors.

Additionally, event objects for different event types contain a subset of the following properties:

• key (number) - The keycode of the keyboard event
• leftButton (boolean) - Flag indicating whether the left button is involved during the event
• middleButton (boolean) - Flag indicating whether the middle button is involved during the event
• rightButton (boolean) - Flag indicating whether the right button is involved during the event
• pointerType (string) - A string indicating the type of input (e.g. 'mouse', 'touch', 'pointer')
• delta (number) - The scroll magnitude/distance of a wheel event