event-flick.js revision 2d6dc2a0e10bdba75ae44aa511c00d3f2b5cb4ff
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholasYUI.add('event-flick', function(Y) {
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas/**
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * Adds support for a "flick" event, which is fired at the end of a touch or mouse based flick gesture, and provides
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * velocity of the flick, along with distance and time information.
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas *
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * @module event-gestures
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * @submodule event-flick
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas */
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas// TODO: Better way to sniff 'n' switch touch support?
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholasvar EVENT = ("ontouchstart" in Y.config.win) ? {
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas start: "touchstart",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas end: "touchend"
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas } : {
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas start: "mousedown",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas end: "mouseup"
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas },
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas START = "start",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas END = "end",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas OWNER_DOCUMENT = "ownerDocument",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas MIN_VELOCITY = "minVelocity",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas MIN_DISTANCE = "minDistance",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas _FLICK_START = "_fs",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas _FLICK_START_HANDLE = "_fsh",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas _FLICK_END_HANDLE = "_feh",
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas NODE_TYPE = "nodeType";
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas/**
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * Sets up a "flick" event, that is fired whenever the user initiates a flick gesture on the node
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * where the listener is attached. The subscriber can specify a minimum distance or velocity for
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * which the event is to be fired.
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas *
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * @event flick
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * @param type {string} "flick"
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * @param fn {function} The method the event invokes.
b33d3bf66f037e3c87d1b857d3706eee0072e0cdNicholas * @param cfg {Object} Optional. An object which specifies the minimum distance and/or velocity
* of the flick gesture for which the event is to be fired.
*
* @return {EventHandle} the detach handle
*/
Y.Event.define('flick', {
init: function (node, subscriber, ce) {
var startHandle = node.on(EVENT[START],
this._onStart,
this,
node,
subscriber,
ce);
node.setData(_FLICK_START_HANDLE, startHandle);
},
destroy: function (node, subscriber, ce) {
var startHandle = node.getData(_FLICK_START_HANDLE),
endHandle = node.getData(_FLICK_END_HANDLE);
if (startHandle) {
startHandle.detach();
node.clearData(_FLICK_START_HANDLE);
}
if (endHandle) {
endHandle.detach();
node.clearData(_FLICK_END_HANDLE);
}
},
processArgs: function(args) {
var params = (args[3]) ? args.splice(3, 1)[0] : {};
if (!(MIN_VELOCITY in params)) {
params.minVelocity = this.MIN_VELOCITY;
}
if (!(MIN_DISTANCE in params)) {
params.minDistance = this.MIN_DISTANCE;
}
return params;
},
_onStart: function(e, node, subscriber, ce) {
var start = true, // always true for mouse
endHandle,
doc,
origE = e;
if (e.touches) {
start = (e.touches.length === 1);
e = e.touches[0];
}
if (start) {
origE.preventDefault();
node.setData(_FLICK_START, {
time : new Date().getTime(),
pageX: e.pageX,
pageY: e.pageY,
clientX: e.clientX,
clientY: e.clientY,
_e : e
});
endHandle = node.getData(_FLICK_END_HANDLE);
if (!endHandle) {
doc = (node.get(NODE_TYPE) === 9) ? node : node.get(OWNER_DOCUMENT);
endHandle = doc.on(EVENT[END], Y.bind(this._onEnd, this), null, node, subscriber, ce);
node.setData(_FLICK_END_HANDLE,endHandle);
}
}
},
_onEnd: function(e, node, subscriber, ce) {
var endTime = new Date().getTime(),
valid = node.getData(_FLICK_START),
start = valid,
endEvent = e,
startTime,
time,
params,
xyDistance,
distance,
absDistance,
velocity,
axis;
if (valid) {
if (e.changedTouches) {
if (e.changedTouches.length === 1 && e.touches.length === 0) {
endEvent = e.changedTouches[0];
} else {
valid = false;
}
}
if (valid) {
endEvent.preventDefault();
startTime = start.time;
endTime = new Date().getTime();
time = endTime - startTime;
params = subscriber._extra;
xyDistance = [
endEvent.pageX - start.pageX,
endEvent.pageY - start.pageY
];
axis = params.axis || (Math.abs(xyDistance[0]) >= Math.abs(xyDistance[1])) ? 'x' : 'y';
distance = xyDistance[(axis === 'x') ? 0 : 1];
absDistance = Math.abs(distance);
velocity = absDistance/time;
if (isFinite(velocity) && velocity >= params.minVelocity && absDistance >= params.minDistance) {
ce.fire({
distance: distance,
time: time,
direction: distance/absDistance,
velocity: velocity,
axis: axis,
button: e.button,
start: start,
end: {
time: endTime,
clientX: endEvent.clientX,
clientY: endEvent.clientY,
pageX: endEvent.pageX,
pageY: endEvent.pageY,
_e : e
}
});
}
node.clearData(_FLICK_START);
}
}
},
MIN_VELOCITY : 0,
MIN_DISTANCE : 10
});
}, '@VERSION@' ,{requires:['node-base','event-touch','event-synthetic']});