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ui.draggable.js
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ui.draggable.js
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/*
* jQuery UI Draggable
*
* Copyright (c) 2008 Paul Bakaus
* Dual licensed under the MIT (MIT-LICENSE.txt)
* and GPL (GPL-LICENSE.txt) licenses.
*
* http://docs.jquery.com/UI/Draggables
*
* Depends:
* ui.core.js
*
* Revision: $Id: ui.draggable.js 5672 2008-05-23 04:11:30Z braeker $
*/
;(function($) {
$.widget("ui.draggable", $.extend($.ui.mouse, {
init: function() {
//Initialize needed constants
var o = this.options;
//Position the node
if(o.helper == 'original' && !(/(relative|absolute|fixed)/).test(this.element.css('position')))
this.element.css('position', 'relative');
this.mouseInit();
},
mouseStart: function(e) {
var o = this.options;
if (o.disabled || $(e.target).is('.ui-resizable-handle')) return false;
var handle = !this.options.handle || !$(this.options.handle, this.element).length ? true : false;
if(!handle) $(this.options.handle, this.element).each(function() {
if(this == e.target) handle = true;
});
if (!handle) return false;
if($.ui.ddmanager) $.ui.ddmanager.current = this;
//Create and append the visible helper
this.helper = $.isFunction(o.helper) ? $(o.helper.apply(this.element[0], [e])) : (o.helper == 'clone' ? this.element.clone() : this.element);
if(!this.helper.parents('body').length) this.helper.appendTo((o.appendTo == 'parent' ? this.element[0].parentNode : o.appendTo));
if(this.helper[0] != this.element[0] && !(/(fixed|absolute)/).test(this.helper.css("position"))) this.helper.css("position", "absolute");
/*
* - Position generation -
* This block generates everything position related - it's the core of draggables.
*/
this.margins = { //Cache the margins
left: (parseInt(this.element.css("marginLeft"),10) || 0),
top: (parseInt(this.element.css("marginTop"),10) || 0)
};
this.cssPosition = this.helper.css("position"); //Store the helper's css position
this.offset = this.element.offset(); //The element's absolute position on the page
this.offset = { //Substract the margins from the element's absolute offset
top: this.offset.top - this.margins.top,
left: this.offset.left - this.margins.left
};
this.offset.click = { //Where the click happened, relative to the element
left: e.pageX - this.offset.left,
top: e.pageY - this.offset.top
};
this.offsetParent = this.helper.offsetParent(); var po = this.offsetParent.offset(); //Get the offsetParent and cache its position
this.offset.parent = { //Store its position plus border
top: po.top + (parseInt(this.offsetParent.css("borderTopWidth"),10) || 0),
left: po.left + (parseInt(this.offsetParent.css("borderLeftWidth"),10) || 0)
};
var p = this.element.position(); //This is a relative to absolute position minus the actual position calculation - only used for relative positioned helpers
this.offset.relative = this.cssPosition == "relative" ? {
top: p.top - (parseInt(this.helper.css("top"),10) || 0) + this.offsetParent[0].scrollTop,
left: p.left - (parseInt(this.helper.css("left"),10) || 0) + this.offsetParent[0].scrollLeft
} : { top: 0, left: 0 };
this.originalPosition = this.generatePosition(e); //Generate the original position
this.helperProportions = { width: this.helper.outerWidth(), height: this.helper.outerHeight() };//Cache the helper size
if(o.cursorAt) {
if(o.cursorAt.left != undefined) this.offset.click.left = o.cursorAt.left;
if(o.cursorAt.right != undefined) this.offset.click.left = this.helperProportions.width - o.cursorAt.right;
if(o.cursorAt.top != undefined) this.offset.click.top = o.cursorAt.top;
if(o.cursorAt.bottom != undefined) this.offset.click.top = this.helperProportions.height - o.cursorAt.bottom;
}
/*
* - Position constraining -
* Here we prepare position constraining like grid and containment.
*/
if(o.containment) {
if(o.containment == 'parent') o.containment = this.helper[0].parentNode;
if(o.containment == 'document') this.containment = [0,0,$(document).width(), ($(document).height() || document.body.parentNode.scrollHeight)];
if(!(/^(document|window|parent)$/).test(o.containment)) {
var ce = $(o.containment)[0];
var co = $(o.containment).offset();
this.containment = [
co.left + (parseInt($(ce).css("borderLeftWidth"),10) || 0) - this.offset.relative.left - this.offset.parent.left,
co.top + (parseInt($(ce).css("borderTopWidth"),10) || 0) - this.offset.relative.top - this.offset.parent.top,
co.left+Math.max(ce.scrollWidth,ce.offsetWidth) - (parseInt($(ce).css("borderLeftWidth"),10) || 0) - this.offset.relative.left - this.offset.parent.left - this.helperProportions.width - this.margins.left - (parseInt(this.element.css("marginRight"),10) || 0),
co.top+Math.max(ce.scrollHeight,ce.offsetHeight) - (parseInt($(ce).css("borderTopWidth"),10) || 0) - this.offset.relative.top - this.offset.parent.top - this.helperProportions.height - this.margins.top - (parseInt(this.element.css("marginBottom"),10) || 0)
];
}
}
//Call plugins and callbacks
this.propagate("start", e);
this.helperProportions = { width: this.helper.outerWidth(), height: this.helper.outerHeight() };//Recache the helper size
if ($.ui.ddmanager && !o.dropBehaviour) $.ui.ddmanager.prepareOffsets(this, e);
this.helper.addClass("ui-draggable-dragging");
this.mouseDrag(e); //Execute the drag once - this causes the helper not to be visible before getting its correct position
return true;
},
convertPositionTo: function(d, pos) {
if(!pos) pos = this.position;
var mod = d == "absolute" ? 1 : -1;
return {
top: (
pos.top // the calculated relative position
+ this.offset.relative.top * mod // Only for relative positioned nodes: Relative offset from element to offset parent
+ this.offset.parent.top * mod // The offsetParent's offset without borders (offset + border)
- (this.cssPosition == "fixed" || (this.cssPosition == "absolute" && this.offsetParent[0] == document.body) ? 0 : this.offsetParent[0].scrollTop) * mod // The offsetParent's scroll position, not if the element is fixed
+ (this.cssPosition == "fixed" ? this.offsetParent[0].scrollTop : 0) * mod
+ this.margins.top * mod //Add the margin (you don't want the margin counting in intersection methods)
),
left: (
pos.left // the calculated relative position
+ this.offset.relative.left * mod // Only for relative positioned nodes: Relative offset from element to offset parent
+ this.offset.parent.left * mod // The offsetParent's offset without borders (offset + border)
- (this.cssPosition == "fixed" || (this.cssPosition == "absolute" && this.offsetParent[0] == document.body) ? 0 : this.offsetParent[0].scrollLeft) * mod // The offsetParent's scroll position, not if the element is fixed
+ (this.cssPosition == "fixed" ? this.offsetParent[0].scrollLeft : 0) * mod
+ this.margins.left * mod //Add the margin (you don't want the margin counting in intersection methods)
)
};
},
generatePosition: function(e) {
var o = this.options;
var position = {
top: (
e.pageY // The absolute mouse position
- this.offset.click.top // Click offset (relative to the element)
- this.offset.relative.top // Only for relative positioned nodes: Relative offset from element to offset parent
- this.offset.parent.top // The offsetParent's offset without borders (offset + border)
+ (this.cssPosition == "fixed" || (this.cssPosition == "absolute" && this.offsetParent[0] == document.body) ? 0 : this.offsetParent[0].scrollTop) // The offsetParent's scroll position, not if the element is fixed
- (this.cssPosition == "fixed" ? this.offsetParent[0].scrollTop : 0)
),
left: (
e.pageX // The absolute mouse position
- this.offset.click.left // Click offset (relative to the element)
- this.offset.relative.left // Only for relative positioned nodes: Relative offset from element to offset parent
- this.offset.parent.left // The offsetParent's offset without borders (offset + border)
+ (this.cssPosition == "fixed" || (this.cssPosition == "absolute" && this.offsetParent[0] == document.body) ? 0 : this.offsetParent[0].scrollLeft) // The offsetParent's scroll position, not if the element is fixed
- (this.cssPosition == "fixed" ? this.offsetParent[0].scrollLeft : 0)
)
};
if(!this.originalPosition) return position; //If we are not dragging yet, we won't check for options
/*
* - Position constraining -
* Constrain the position to a mix of grid, containment.
*/
if(this.containment) {
if(position.left < this.containment[0]) position.left = this.containment[0];
if(position.top < this.containment[1]) position.top = this.containment[1];
if(position.left > this.containment[2]) position.left = this.containment[2];
if(position.top > this.containment[3]) position.top = this.containment[3];
}
if(o.grid) {
var top = this.originalPosition.top + Math.round((position.top - this.originalPosition.top) / o.grid[1]) * o.grid[1];
position.top = this.containment ? (!(top < this.containment[1] || top > this.containment[3]) ? top : (!(top < this.containment[1]) ? top - o.grid[1] : top + o.grid[1])) : top;
var left = this.originalPosition.left + Math.round((position.left - this.originalPosition.left) / o.grid[0]) * o.grid[0];
position.left = this.containment ? (!(left < this.containment[0] || left > this.containment[2]) ? left : (!(left < this.containment[0]) ? left - o.grid[0] : left + o.grid[0])) : left;
}
return position;
},
mouseDrag: function(e) {
//Compute the helpers position
this.position = this.generatePosition(e);
this.positionAbs = this.convertPositionTo("absolute");
//Call plugins and callbacks and use the resulting position if something is returned
this.position = this.propagate("drag", e) || this.position;
if(!this.options.axis || this.options.axis == "x") this.helper[0].style.left = this.position.left+'px';
if(!this.options.axis || this.options.axis == "y") this.helper[0].style.top = this.position.top+'px';
if($.ui.ddmanager) $.ui.ddmanager.drag(this, e);
return false;
},
mouseStop: function(e) {
//If we are using droppables, inform the manager about the drop
if ($.ui.ddmanager && !this.options.dropBehaviour)
$.ui.ddmanager.drop(this, e);
if(this.options.revert) {
var self = this;
$(this.helper).animate(this.originalPosition, parseInt(this.options.revert, 10) || 500, function() {
self.propagate("stop", e);
self.clear();
});
} else {
this.propagate("stop", e);
this.clear();
}
return false;
},
clear: function() {
this.helper.removeClass("ui-draggable-dragging");
if(this.options.helper != 'original' && !this.cancelHelperRemoval) this.helper.remove();
if($.ui.ddmanager) $.ui.ddmanager.current = null;
this.helper = null;
this.cancelHelperRemoval = false;
},
// From now on bulk stuff - mainly helpers
plugins: {},
uiHash: function(e) {
return {
helper: this.helper,
position: this.position,
absolutePosition: this.positionAbs,
options: this.options
};
},
propagate: function(n,e) {
$.ui.plugin.call(this, n, [e, this.uiHash()]);
return this.element.triggerHandler(n == "drag" ? n : "drag"+n, [e, this.uiHash()], this.options[n]);
},
destroy: function() {
if(!this.element.data('draggable')) return;
this.element.removeData("draggable").unbind(".draggable");
this.mouseDestroy();
}
}));
$.extend($.ui.draggable, {
defaults: {
distance: 0,
delay: 0,
cancel: ":input,button",
helper: "original",
appendTo: "parent"
}
});
$.ui.plugin.add("draggable", "cursor", {
start: function(e, ui) {
var t = $('body');
if (t.css("cursor")) ui.options._cursor = t.css("cursor");
t.css("cursor", ui.options.cursor);
},
stop: function(e, ui) {
if (ui.options._cursor) $('body').css("cursor", ui.options._cursor);
}
});
$.ui.plugin.add("draggable", "zIndex", {
start: function(e, ui) {
var t = $(ui.helper);
if(t.css("zIndex")) ui.options._zIndex = t.css("zIndex");
t.css('zIndex', ui.options.zIndex);
},
stop: function(e, ui) {
if(ui.options._zIndex) $(ui.helper).css('zIndex', ui.options._zIndex);
}
});
$.ui.plugin.add("draggable", "opacity", {
start: function(e, ui) {
var t = $(ui.helper);
if(t.css("opacity")) ui.options._opacity = t.css("opacity");
t.css('opacity', ui.options.opacity);
},
stop: function(e, ui) {
if(ui.options._opacity) $(ui.helper).css('opacity', ui.options._opacity);
}
});
$.ui.plugin.add("draggable", "iframeFix", {
start: function(e, ui) {
$(ui.options.iframeFix === true ? "iframe" : ui.options.iframeFix).each(function() {
$('<div class="ui-draggable-iframeFix" style="background: #fff;"></div>')
.css({
width: this.offsetWidth+"px", height: this.offsetHeight+"px",
position: "absolute", opacity: "0.001", zIndex: 1000
})
.css($(this).offset())
.appendTo("body");
});
},
stop: function(e, ui) {
$("div.DragDropIframeFix").each(function() { this.parentNode.removeChild(this); }); //Remove frame helpers
}
});
$.ui.plugin.add("draggable", "scroll", {
start: function(e, ui) {
var o = ui.options;
var i = $(this).data("draggable");
o.scrollSensitivity = o.scrollSensitivity || 20;
o.scrollSpeed = o.scrollSpeed || 20;
i.overflowY = function(el) {
do { if(/auto|scroll/.test(el.css('overflow')) || (/auto|scroll/).test(el.css('overflow-y'))) return el; el = el.parent(); } while (el[0].parentNode);
return $(document);
}(this);
i.overflowX = function(el) {
do { if(/auto|scroll/.test(el.css('overflow')) || (/auto|scroll/).test(el.css('overflow-x'))) return el; el = el.parent(); } while (el[0].parentNode);
return $(document);
}(this);
if(i.overflowY[0] != document && i.overflowY[0].tagName != 'HTML') i.overflowYOffset = i.overflowY.offset();
if(i.overflowX[0] != document && i.overflowX[0].tagName != 'HTML') i.overflowXOffset = i.overflowX.offset();
},
drag: function(e, ui) {
var o = ui.options;
var i = $(this).data("draggable");
if(i.overflowY[0] != document && i.overflowY[0].tagName != 'HTML') {
if((i.overflowYOffset.top + i.overflowY[0].offsetHeight) - e.pageY < o.scrollSensitivity)
i.overflowY[0].scrollTop = i.overflowY[0].scrollTop + o.scrollSpeed;
if(e.pageY - i.overflowYOffset.top < o.scrollSensitivity)
i.overflowY[0].scrollTop = i.overflowY[0].scrollTop - o.scrollSpeed;
} else {
if(e.pageY - $(document).scrollTop() < o.scrollSensitivity)
$(document).scrollTop($(document).scrollTop() - o.scrollSpeed);
if($(window).height() - (e.pageY - $(document).scrollTop()) < o.scrollSensitivity)
$(document).scrollTop($(document).scrollTop() + o.scrollSpeed);
}
if(i.overflowX[0] != document && i.overflowX[0].tagName != 'HTML') {
if((i.overflowXOffset.left + i.overflowX[0].offsetWidth) - e.pageX < o.scrollSensitivity)
i.overflowX[0].scrollLeft = i.overflowX[0].scrollLeft + o.scrollSpeed;
if(e.pageX - i.overflowXOffset.left < o.scrollSensitivity)
i.overflowX[0].scrollLeft = i.overflowX[0].scrollLeft - o.scrollSpeed;
} else {
if(e.pageX - $(document).scrollLeft() < o.scrollSensitivity)
$(document).scrollLeft($(document).scrollLeft() - o.scrollSpeed);
if($(window).width() - (e.pageX - $(document).scrollLeft()) < o.scrollSensitivity)
$(document).scrollLeft($(document).scrollLeft() + o.scrollSpeed);
}
}
});
$.ui.plugin.add("draggable", "snap", {
start: function(e, ui) {
var inst = $(this).data("draggable");
inst.snapElements = [];
$(ui.options.snap === true ? '.ui-draggable' : ui.options.snap).each(function() {
var $t = $(this); var $o = $t.offset();
if(this != inst.element[0]) inst.snapElements.push({
item: this,
width: $t.outerWidth(), height: $t.outerHeight(),
top: $o.top, left: $o.left
});
});
},
drag: function(e, ui) {
var inst = $(this).data("draggable");
var d = ui.options.snapTolerance || 20;
var x1 = ui.absolutePosition.left, x2 = x1 + inst.helperProportions.width,
y1 = ui.absolutePosition.top, y2 = y1 + inst.helperProportions.height;
for (var i = inst.snapElements.length - 1; i >= 0; i--){
var l = inst.snapElements[i].left, r = l + inst.snapElements[i].width,
t = inst.snapElements[i].top, b = t + inst.snapElements[i].height;
//Yes, I know, this is insane ;)
if(!((l-d < x1 && x1 < r+d && t-d < y1 && y1 < b+d) || (l-d < x1 && x1 < r+d && t-d < y2 && y2 < b+d) || (l-d < x2 && x2 < r+d && t-d < y1 && y1 < b+d) || (l-d < x2 && x2 < r+d && t-d < y2 && y2 < b+d))) continue;
if(ui.options.snapMode != 'inner') {
var ts = Math.abs(t - y2) <= 20;
var bs = Math.abs(b - y1) <= 20;
var ls = Math.abs(l - x2) <= 20;
var rs = Math.abs(r - x1) <= 20;
if(ts) ui.position.top = inst.convertPositionTo("relative", { top: t - inst.helperProportions.height, left: 0 }).top;
if(bs) ui.position.top = inst.convertPositionTo("relative", { top: b, left: 0 }).top;
if(ls) ui.position.left = inst.convertPositionTo("relative", { top: 0, left: l - inst.helperProportions.width }).left;
if(rs) ui.position.left = inst.convertPositionTo("relative", { top: 0, left: r }).left;
}
if(ui.options.snapMode != 'outer') {
var ts = Math.abs(t - y1) <= 20;
var bs = Math.abs(b - y2) <= 20;
var ls = Math.abs(l - x1) <= 20;
var rs = Math.abs(r - x2) <= 20;
if(ts) ui.position.top = inst.convertPositionTo("relative", { top: t, left: 0 }).top;
if(bs) ui.position.top = inst.convertPositionTo("relative", { top: b - inst.helperProportions.height, left: 0 }).top;
if(ls) ui.position.left = inst.convertPositionTo("relative", { top: 0, left: l }).left;
if(rs) ui.position.left = inst.convertPositionTo("relative", { top: 0, left: r - inst.helperProportions.width }).left;
}
};
}
});
$.ui.plugin.add("draggable", "connectToSortable", {
start: function(e,ui) {
var inst = $(this).data("draggable");
inst.sortables = [];
$(ui.options.connectToSortable).each(function() {
if($.data(this, 'sortable')) inst.sortables.push({
instance: $.data(this, 'sortable'),
offset: $.data(this, 'sortable').element.offset(),
width: $.data(this, 'sortable').element.width(),
height: $.data(this, 'sortable').element.height(),
shouldRevert: $.data(this, 'sortable').options.revert
});
});
},
stop: function(e,ui) {
//If we are still over the sortable, we fake the stop event of the sortable, but also remove helper
var inst = $(this).data("draggable");
$.each(inst.sortables, function() {
if(this.instance.isOver) {
this.instance.isOver = 0;
inst.cancelHelperRemoval = true; //Don't remove the helper in the draggable instance
this.instance.cancelHelperRemoval = false; //Remove it in the sortable instance (so sortable plugins like revert still work)
if(this.shouldRevert) this.instance.options.revert = true; //revert here
this.instance.mouseStop(e);
this.instance.options.helper = "original";
}
});
},
drag: function(e,ui) {
//This is handy: We reuse the intersectsWith method for checking if the current draggable helper
//intersects with the sortable container
var inst = $(this).data("draggable"), self = this;
inst.position.absolute = ui.absolutePosition; //Sorry, this is an ugly API fix
var checkPos = function(o) {
var l = o.left, r = l + o.width,
t = o.top, b = t + o.height;
return (l < (this.position.absolute.left + this.offset.click.left) && (this.position.absolute.left + this.offset.click.left) < r
&& t < (this.position.absolute.top + this.offset.click.top) && (this.position.absolute.top + this.offset.click.top) < b);
};
$.each(inst.sortables, function() {
if(checkPos.call(inst, {
left: this.offset.left, top: this.offset.top,
width: this.width, height: this.height
})) {
//If it intersects, we use a little isOver variable and set it once, so our move-in stuff gets fired only once
if(!this.instance.isOver) {
this.instance.isOver = 1;
//Now we fake the start of dragging for the sortable instance,
//by cloning the list group item, appending it to the sortable and using it as inst.currentItem
//We can then fire the start event of the sortable with our passed browser event, and our own helper (so it doesn't create a new one)
this.instance.currentItem = $(self).clone().appendTo(this.instance.element).data("sortable-item", true);
this.instance.options.helper = function() { return ui.helper[0]; };
e.target = this.instance.currentItem[0];
this.instance.mouseStart(e, true);
//Because the browser event is way off the new appended portlet, we modify a couple of variables to reflect the changes
this.instance.clickOffset.top = inst.offset.click.top;
this.instance.clickOffset.left = inst.offset.click.left;
this.instance.offset.left -= ui.absolutePosition.left - this.instance.position.absolute.left;
this.instance.offset.top -= ui.absolutePosition.top - this.instance.position.absolute.top;
inst.propagate("toSortable", e);
}
//Provided we did all the previous steps, we can fire the drag event of the sortable on every draggable drag, when it intersects with the sortable
if(this.instance.currentItem) this.instance.mouseDrag(e);
} else {
//If it doesn't intersect with the sortable, and it intersected before,
//we fake the drag stop of the sortable, but make sure it doesn't remove the helper by using cancelHelperRemoval
if(this.instance.isOver) {
this.instance.isOver = 0;
this.instance.cancelHelperRemoval = true;
this.instance.options.revert = false; //No revert here
this.instance.mouseStop(e);
this.instance.options.helper = "original";
//Now we remove our currentItem, the list group clone again, and the placeholder, and animate the helper back to it's original size
this.instance.currentItem.remove();
this.instance.placeholder.remove();
inst.propagate("fromSortable", e);
}
};
});
}
});
$.ui.plugin.add("draggable", "stack", {
start: function(e,ui) {
var group = $.makeArray($(ui.options.stack.group)).sort(function(a,b) {
return (parseInt($(a).css("zIndex"),10) || ui.options.stack.min) - (parseInt($(b).css("zIndex"),10) || ui.options.stack.min);
});
$(group).each(function(i) {
this.style.zIndex = ui.options.stack.min + i;
});
this[0].style.zIndex = ui.options.stack.min + group.length;
}
});
})(jQuery);