3
Copyright 2011 Yahoo! Inc. All rights reserved.
4
Licensed under the BSD License.
5
http://yuilibrary.com/license/
7
YUI.add('dd-constrain', function(Y) {
11
* The Drag & Drop Utility allows you to create a draggable interface efficiently, buffering you from browser-level abnormalities and enabling you to focus on the interesting logic surrounding your particular implementation. This component enables you to create a variety of standard draggable objects with just a few lines of code and then, using its extensive API, add your own specific implementation logic.
14
* @submodule dd-constrain
17
* Plugin for the dd-drag module to add the constraining methods to it. It supports constraining to a node or viewport. It supports tick based moves and XY axis constraints.
18
* @class DDConstrained
24
var DRAG_NODE = 'dragNode',
25
OFFSET_HEIGHT = 'offsetHeight',
26
OFFSET_WIDTH = 'offsetWidth',
28
TICK_X_ARRAY = 'tickXArray',
29
TICK_Y_ARRAY = 'tickYArray',
39
* @event drag:tickAlignX
40
* @description Fires when this node is aligned with the tickX value.
41
* @param {EventFacade} event An Event Facade object
44
EV_TICK_ALIGN_X = 'drag:tickAlignX',
47
* @event drag:tickAlignY
48
* @description Fires when this node is aligned with the tickY value.
49
* @param {EventFacade} event An Event Facade object
52
EV_TICK_ALIGN_Y = 'drag:tickAlignY',
54
C = function(config) {
55
this._lazyAddAttrs = false;
56
C.superclass.constructor.apply(this, arguments);
59
C.NAME = 'ddConstrained';
66
* @description The Constrained instance will be placed on the Drag instance under the con namespace.
76
* @description Stick the drag movement to the X-Axis. Default: false
84
* @description Stick the drag movement to the Y-Axis
92
* @description The X tick offset the drag node should snap to on each drag move. False for no ticks. Default: false
100
* @description The Y tick offset the drag node should snap to on each drag move. False for no ticks. Default: false
107
* @attribute tickXArray
108
* @description An array of page coordinates to use as X ticks for drag movement.
115
* @attribute tickYArray
116
* @description An array of page coordinates to use as Y ticks for drag movement.
124
* @description CSS style string for the gutter of a region (supports negative values): '5 0' (sets top and bottom to 5px, left and right to 0px), '1 2 3 4' (top 1px, right 2px, bottom 3px, left 4px)
129
setter: function(gutter) {
130
return Y.DD.DDM.cssSizestoObject(gutter);
134
* @attribute constrain
135
* @description Will attempt to constrain the drag node to the boundaries. Arguments:<br>
136
* 'view': Contrain to Viewport<br>
137
* '#selector_string': Constrain to this node<br>
138
* '{Region Object}': An Object Literal containing a valid region (top, right, bottom, left) of page positions
139
* @type {String/Object/Node}
143
setter: function(con) {
144
var node = Y.one(con);
153
* @attribute constrain2region
154
* @description An Object Literal containing a valid region (top, right, bottom, left) of page positions to constrain the drag node to.
158
setter: function(r) {
159
return this.set('constrain', r);
164
* @attribute constrain2node
165
* @description Will attempt to constrain the drag node to the boundaries of this node.
169
setter: function(n) {
170
return this.set('constrain', Y.one(n));
175
* @attribute constrain2view
176
* @description Will attempt to constrain the drag node to the boundaries of the viewport region.
180
setter: function(n) {
181
return this.set('constrain', VIEW);
185
* @attribute cacheRegion
186
* @description Should the region be cached for performace. Default: true
195
_lastTickXFired: null,
196
_lastTickYFired: null,
198
initializer: function() {
199
this._createEvents();
201
this.get(HOST).on('drag:end', Y.bind(this._handleEnd, this));
202
this.get(HOST).on('drag:start', Y.bind(this._handleStart, this));
203
this.get(HOST).after('drag:align', Y.bind(this.align, this));
204
this.get(HOST).after('drag:drag', Y.bind(this.drag, this));
208
* @method _createEvents
209
* @description This method creates all the events for this Event Target and publishes them so we get Event Bubbling.
211
_createEvents: function() {
219
Y.each(ev, function(v, k) {
232
* @description Fires on drag:end
234
_handleEnd: function() {
235
this._lastTickYFired = null;
236
this._lastTickXFired = null;
240
* @method _handleStart
241
* @description Fires on drag:start and clears the _regionCache
243
_handleStart: function() {
248
* @property _regionCache
249
* @description Store a cache of the region that we are constraining to
255
* @method _cacheRegion
256
* @description Get's the region and caches it, called from window.resize and when the cache is null
258
_cacheRegion: function() {
259
this._regionCache = this.get('constrain').get('region');
263
* @description Reset the internal region cache.
265
resetCache: function() {
266
this._regionCache = null;
270
* @method _getConstraint
271
* @description Standardizes the 'constraint' attribute
273
_getConstraint: function() {
274
var con = this.get('constrain'),
275
g = this.get('gutter'),
279
if (con instanceof Y.Node) {
280
if (!this._regionCache) {
281
Y.on('resize', Y.bind(this._cacheRegion, this), Y.config.win);
284
region = Y.clone(this._regionCache);
285
if (!this.get('cacheRegion')) {
288
} else if (Y.Lang.isObject(con)) {
289
region = Y.clone(con);
292
if (!con || !region) {
296
region = this.get(HOST).get(DRAG_NODE).get('viewportRegion');
299
Y.each(g, function(i, n) {
300
if ((n == RIGHT) || (n == BOTTOM)) {
311
* @description Get the active region: viewport, node, custom region
312
* @param {Boolean} inc Include the node's height and width
315
getRegion: function(inc) {
316
var r = {}, oh = null, ow = null,
317
host = this.get(HOST);
319
r = this._getConstraint();
322
oh = host.get(DRAG_NODE).get(OFFSET_HEIGHT);
323
ow = host.get(DRAG_NODE).get(OFFSET_WIDTH);
324
r[RIGHT] = r[RIGHT] - ow;
325
r[BOTTOM] = r[BOTTOM] - oh;
331
* @method _checkRegion
332
* @description Check if xy is inside a given region, if not change to it be inside.
333
* @param {Array} _xy The XY to check if it's in the current region, if it isn't inside the region, it will reset the xy array to be inside the region.
334
* @return {Array} The new XY that is inside the region
336
_checkRegion: function(_xy) {
338
r = this.getRegion(),
339
host = this.get(HOST),
340
oh = host.get(DRAG_NODE).get(OFFSET_HEIGHT),
341
ow = host.get(DRAG_NODE).get(OFFSET_WIDTH);
343
if (oxy[1] > (r[BOTTOM] - oh)) {
344
_xy[1] = (r[BOTTOM] - oh);
346
if (r[TOP] > oxy[1]) {
350
if (oxy[0] > (r[RIGHT] - ow)) {
351
_xy[0] = (r[RIGHT] - ow);
353
if (r[LEFT] > oxy[0]) {
361
* @description Checks if the XY passed or the dragNode is inside the active region.
362
* @param {Array} xy Optional XY to check, if not supplied this.get('dragNode').getXY() is used.
363
* @return {Boolean} True if the XY is inside the region, false otherwise.
365
inRegion: function(xy) {
366
xy = xy || this.get(HOST).get(DRAG_NODE).getXY();
368
var _xy = this._checkRegion([xy[0], xy[1]]),
370
if ((xy[0] === _xy[0]) && (xy[1] === _xy[1])) {
377
* @description Modifies the Drag.actXY method from the after drag:align event. This is where the constraining happens.
380
var host = this.get(HOST),
381
_xy = [host.actXY[0], host.actXY[1]],
382
r = this.getRegion(true);
384
if (this.get('stickX')) {
385
_xy[1] = (host.startXY[1] - host.deltaXY[1]);
387
if (this.get('stickY')) {
388
_xy[0] = (host.startXY[0] - host.deltaXY[0]);
392
_xy = this._checkRegion(_xy);
395
_xy = this._checkTicks(_xy, r);
401
* @description Fires after drag:drag. Handle the tickX and tickX align events.
403
drag: function(event) {
404
var host = this.get(HOST),
405
xt = this.get('tickX'),
406
yt = this.get('tickY'),
407
_xy = [host.actXY[0], host.actXY[1]];
409
if ((Y.Lang.isNumber(xt) || this.get(TICK_X_ARRAY)) && (this._lastTickXFired !== _xy[0])) {
411
this._lastTickXFired = _xy[0];
414
if ((Y.Lang.isNumber(yt) || this.get(TICK_Y_ARRAY)) && (this._lastTickYFired !== _xy[1])) {
416
this._lastTickYFired = _xy[1];
421
* @method _checkTicks
422
* @description This method delegates the proper helper method for tick calculations
423
* @param {Array} xy The XY coords for the Drag
424
* @param {Object} r The optional region that we are bound to.
425
* @return {Array} The calced XY coords
427
_checkTicks: function(xy, r) {
428
var host = this.get(HOST),
429
lx = (host.startXY[0] - host.deltaXY[0]),
430
ly = (host.startXY[1] - host.deltaXY[1]),
431
xt = this.get('tickX'),
432
yt = this.get('tickY');
433
if (xt && !this.get(TICK_X_ARRAY)) {
434
xy[0] = DDM._calcTicks(xy[0], lx, xt, r[LEFT], r[RIGHT]);
436
if (yt && !this.get(TICK_Y_ARRAY)) {
437
xy[1] = DDM._calcTicks(xy[1], ly, yt, r[TOP], r[BOTTOM]);
439
if (this.get(TICK_X_ARRAY)) {
440
xy[0] = DDM._calcTickArray(xy[0], this.get(TICK_X_ARRAY), r[LEFT], r[RIGHT]);
442
if (this.get(TICK_Y_ARRAY)) {
443
xy[1] = DDM._calcTickArray(xy[1], this.get(TICK_Y_ARRAY), r[TOP], r[BOTTOM]);
450
* @method _tickAlignX
451
* @description Fires when the actXY[0] reach a new value respecting the tickX gap.
453
_tickAlignX: function() {
454
this.fire(EV_TICK_ALIGN_X);
458
* @method _tickAlignY
459
* @description Fires when the actXY[1] reach a new value respecting the tickY gap.
461
_tickAlignY: function() {
462
this.fire(EV_TICK_ALIGN_Y);
466
Y.namespace('Plugin');
467
Y.extend(C, Y.Base, proto);
468
Y.Plugin.DDConstrained = C;
476
* @description Helper method to calculate the tick offsets for a given position
477
* @param {Number} pos The current X or Y position
478
* @param {Number} start The start X or Y position
479
* @param {Number} tick The X or Y tick increment
480
* @param {Number} off1 The min offset that we can't pass (region)
481
* @param {Number} off2 The max offset that we can't pass (region)
482
* @return {Number} The new position based on the tick calculation
484
_calcTicks: function(pos, start, tick, off1, off2) {
485
var ix = ((pos - start) / tick),
486
min = Math.floor(ix),
488
if ((min !== 0) || (max !== 0)) {
489
if ((ix >= min) && (ix <= max)) {
490
pos = (start + (tick * min));
493
pos = (start + (tick * (min + 1)));
496
pos = (start + (tick * (min - 1)));
507
* @method _calcTickArray
508
* @description This method is used with the tickXArray and tickYArray config options
509
* @param {Number} pos The current X or Y position
510
* @param {Number} ticks The array containing our custom tick positions.
511
* @param {Number} off1 The min offset that we can't pass (region)
512
* @param {Number} off2 The max offset that we can't pass (region)
513
* @return The tick position
515
_calcTickArray: function(pos, ticks, off1, off2) {
516
var i = 0, len = ticks.length, next = 0,
519
if (!ticks || (ticks.length === 0)) {
521
} else if (ticks[0] >= pos) {
524
for (i = 0; i < len; i++) {
526
if (ticks[next] && ticks[next] >= pos) {
527
diff1 = pos - ticks[i];
528
diff2 = ticks[next] - pos;
529
ret = (diff2 > diff1) ? ticks[i] : ticks[next];
535
ret = ticks[len - 1];
543
return ticks[ticks.length - 1];
550
}, '3.4.1' ,{skinnable:false, requires:['dd-drag']});