app/assets/javascripts/jquery.event.drag-2.2.js
/*!
* jquery.event.drag - v 2.2
* Copyright (c) 2010 Three Dub Media - http://threedubmedia.com
* Open Source MIT License - http://threedubmedia.com/code/license
*/
// Created: 2008-06-04
// Updated: 2012-05-21
// REQUIRES: jquery 1.7.x
;(function( $ ){
// add the jquery instance method
$.fn.drag = function( str, arg, opts ){
// figure out the event type
var type = typeof str == "string" ? str : "",
// figure out the event handler...
fn = $.isFunction( str ) ? str : $.isFunction( arg ) ? arg : null;
// fix the event type
if ( type.indexOf("drag") !== 0 )
type = "drag"+ type;
// were options passed
opts = ( str == fn ? arg : opts ) || {};
// trigger or bind event handler
return fn ? this.bind( type, opts, fn ) : this.trigger( type );
};
// local refs (increase compression)
var $event = $.event,
$special = $event.special,
// configure the drag special event
drag = $special.drag = {
// these are the default settings
defaults: {
which: 1, // mouse button pressed to start drag sequence
distance: 0, // distance dragged before dragstart
not: ':input', // selector to suppress dragging on target elements
handle: null, // selector to match handle target elements
relative: false, // true to use "position", false to use "offset"
drop: true, // false to suppress drop events, true or selector to allow
click: false // false to suppress click events after dragend (no proxy)
},
// the key name for stored drag data
datakey: "dragdata",
// prevent bubbling for better performance
noBubble: true,
// count bound related events
add: function( obj ){
// read the interaction data
var data = $.data( this, drag.datakey ),
// read any passed options
opts = obj.data || {};
// count another realted event
data.related += 1;
// extend data options bound with this event
// don't iterate "opts" in case it is a node
$.each( drag.defaults, function( key, def ){
if ( opts[ key ] !== undefined )
data[ key ] = opts[ key ];
});
},
// forget unbound related events
remove: function(){
$.data( this, drag.datakey ).related -= 1;
},
// configure interaction, capture settings
setup: function(){
// check for related events
if ( $.data( this, drag.datakey ) )
return;
// initialize the drag data with copied defaults
var data = $.extend({ related:0 }, drag.defaults );
// store the interaction data
$.data( this, drag.datakey, data );
// bind the mousedown event, which starts drag interactions
$event.add( this, "touchstart mousedown", drag.init, data );
// prevent image dragging in IE...
if ( this.attachEvent )
this.attachEvent("ondragstart", drag.dontstart );
},
// destroy configured interaction
teardown: function(){
var data = $.data( this, drag.datakey ) || {};
// check for related events
if ( data.related )
return;
// remove the stored data
$.removeData( this, drag.datakey );
// remove the mousedown event
$event.remove( this, "touchstart mousedown", drag.init );
// enable text selection
drag.textselect( true );
// un-prevent image dragging in IE...
if ( this.detachEvent )
this.detachEvent("ondragstart", drag.dontstart );
},
// initialize the interaction
init: function( event ){
// sorry, only one touch at a time
if ( drag.touched )
return;
// the drag/drop interaction data
var dd = event.data, results;
// check the which directive
if ( event.which != 0 && dd.which > 0 && event.which != dd.which )
return;
// check for suppressed selector
if ( $( event.target ).is( dd.not ) )
return;
// check for handle selector
if ( dd.handle && !$( event.target ).closest( dd.handle, event.currentTarget ).length )
return;
drag.touched = event.type == 'touchstart' ? this : null;
dd.propagates = 1;
dd.mousedown = this;
dd.interactions = [ drag.interaction( this, dd ) ];
dd.target = event.target;
dd.pageX = event.pageX;
dd.pageY = event.pageY;
dd.dragging = null;
// handle draginit event...
results = drag.hijack( event, "draginit", dd );
// early cancel
if ( !dd.propagates )
return;
// flatten the result set
results = drag.flatten( results );
// insert new interaction elements
if ( results && results.length ){
dd.interactions = [];
$.each( results, function(){
dd.interactions.push( drag.interaction( this, dd ) );
});
}
// remember how many interactions are propagating
dd.propagates = dd.interactions.length;
// locate and init the drop targets
if ( dd.drop !== false && $special.drop )
$special.drop.handler( event, dd );
// disable text selection
drag.textselect( false );
// bind additional events...
if ( drag.touched )
$event.add( drag.touched, "touchmove touchend", drag.handler, dd );
else
$event.add( document, "mousemove mouseup", drag.handler, dd );
// helps prevent text selection or scrolling
if ( !drag.touched || dd.live )
return false;
},
// returns an interaction object
interaction: function( elem, dd ){
var offset = $( elem )[ dd.relative ? "position" : "offset" ]() || { top:0, left:0 };
return {
drag: elem,
callback: new drag.callback(),
droppable: [],
offset: offset
};
},
// handle drag-releatd DOM events
handler: function( event ){
// read the data before hijacking anything
var dd = event.data;
// handle various events
switch ( event.type ){
// mousemove, check distance, start dragging
case !dd.dragging && 'touchmove':
event.preventDefault();
case !dd.dragging && 'mousemove':
// drag tolerance, x² + y² = distance²
if ( Math.pow( event.pageX-dd.pageX, 2 ) + Math.pow( event.pageY-dd.pageY, 2 ) < Math.pow( dd.distance, 2 ) )
break; // distance tolerance not reached
event.target = dd.target; // force target from "mousedown" event (fix distance issue)
drag.hijack( event, "dragstart", dd ); // trigger "dragstart"
if ( dd.propagates ) // "dragstart" not rejected
dd.dragging = true; // activate interaction
// mousemove, dragging
case 'touchmove':
event.preventDefault();
case 'mousemove':
if ( dd.dragging ){
// trigger "drag"
drag.hijack( event, "drag", dd );
if ( dd.propagates ){
// manage drop events
if ( dd.drop !== false && $special.drop )
$special.drop.handler( event, dd ); // "dropstart", "dropend"
break; // "drag" not rejected, stop
}
event.type = "mouseup"; // helps "drop" handler behave
}
// mouseup, stop dragging
case 'touchend':
case 'mouseup':
default:
if ( drag.touched )
$event.remove( drag.touched, "touchmove touchend", drag.handler ); // remove touch events
else
$event.remove( document, "mousemove mouseup", drag.handler ); // remove page events
if ( dd.dragging ){
if ( dd.drop !== false && $special.drop )
$special.drop.handler( event, dd ); // "drop"
drag.hijack( event, "dragend", dd ); // trigger "dragend"
}
drag.textselect( true ); // enable text selection
// if suppressing click events...
if ( dd.click === false && dd.dragging )
$.data( dd.mousedown, "suppress.click", new Date().getTime() + 5 );
dd.dragging = drag.touched = false; // deactivate element
break;
}
},
// re-use event object for custom events
hijack: function( event, type, dd, x, elem ){
// not configured
if ( !dd )
return;
// remember the original event and type
var orig = { event:event.originalEvent, type:event.type },
// is the event drag related or drog related?
mode = type.indexOf("drop") ? "drag" : "drop",
// iteration vars
result, i = x || 0, ia, $elems, callback,
len = !isNaN( x ) ? x : dd.interactions.length;
// modify the event type
event.type = type;
// remove the original event
event.originalEvent = null;
// initialize the results
dd.results = [];
// handle each interacted element
do if ( ia = dd.interactions[ i ] ){
// validate the interaction
if ( type !== "dragend" && ia.cancelled )
continue;
// set the dragdrop properties on the event object
callback = drag.properties( event, dd, ia );
// prepare for more results
ia.results = [];
// handle each element
$( elem || ia[ mode ] || dd.droppable ).each(function( p, subject ){
// identify drag or drop targets individually
callback.target = subject;
// force propagtion of the custom event
event.isPropagationStopped = function(){ return false; };
// handle the event
result = subject ? $event.dispatch.call( subject, event, callback ) : null;
// stop the drag interaction for this element
if ( result === false ){
if ( mode == "drag" ){
ia.cancelled = true;
dd.propagates -= 1;
}
if ( type == "drop" ){
ia[ mode ][p] = null;
}
}
// assign any dropinit elements
else if ( type == "dropinit" )
ia.droppable.push( drag.element( result ) || subject );
// accept a returned proxy element
if ( type == "dragstart" )
ia.proxy = $( drag.element( result ) || ia.drag )[0];
// remember this result
ia.results.push( result );
// forget the event result, for recycling
delete event.result;
// break on cancelled handler
if ( type !== "dropinit" )
return result;
});
// flatten the results
dd.results[ i ] = drag.flatten( ia.results );
// accept a set of valid drop targets
if ( type == "dropinit" )
ia.droppable = drag.flatten( ia.droppable );
// locate drop targets
if ( type == "dragstart" && !ia.cancelled )
callback.update();
}
while ( ++i < len )
// restore the original event & type
event.type = orig.type;
event.originalEvent = orig.event;
// return all handler results
return drag.flatten( dd.results );
},
// extend the callback object with drag/drop properties...
properties: function( event, dd, ia ){
var obj = ia.callback;
// elements
obj.drag = ia.drag;
obj.proxy = ia.proxy || ia.drag;
// starting mouse position
obj.startX = dd.pageX;
obj.startY = dd.pageY;
// current distance dragged
obj.deltaX = event.pageX - dd.pageX;
obj.deltaY = event.pageY - dd.pageY;
// original element position
obj.originalX = ia.offset.left;
obj.originalY = ia.offset.top;
// adjusted element position
obj.offsetX = obj.originalX + obj.deltaX;
obj.offsetY = obj.originalY + obj.deltaY;
// assign the drop targets information
obj.drop = drag.flatten( ( ia.drop || [] ).slice() );
obj.available = drag.flatten( ( ia.droppable || [] ).slice() );
return obj;
},
// determine is the argument is an element or jquery instance
element: function( arg ){
if ( arg && ( arg.jquery || arg.nodeType == 1 ) )
return arg;
},
// flatten nested jquery objects and arrays into a single dimension array
flatten: function( arr ){
return $.map( arr, function( member ){
return member && member.jquery ? $.makeArray( member ) :
member && member.length ? drag.flatten( member ) : member;
});
},
// toggles text selection attributes ON (true) or OFF (false)
textselect: function( bool ){
$( document )[ bool ? "unbind" : "bind" ]("selectstart", drag.dontstart )
.css("MozUserSelect", bool ? "" : "none" );
// .attr("unselectable", bool ? "off" : "on" )
document.unselectable = bool ? "off" : "on";
},
// suppress "selectstart" and "ondragstart" events
dontstart: function(){
return false;
},
// a callback instance contructor
callback: function(){}
};
// callback methods
drag.callback.prototype = {
update: function(){
if ( $special.drop && this.available.length )
$.each( this.available, function( i ){
$special.drop.locate( this, i );
});
}
};
// patch $.event.$dispatch to allow suppressing clicks
var $dispatch = $event.dispatch;
$event.dispatch = function( event ){
if ( $.data( this, "suppress."+ event.type ) - new Date().getTime() > 0 ){
$.removeData( this, "suppress."+ event.type );
return;
}
return $dispatch.apply( this, arguments );
};
// event fix hooks for touch events...
var touchHooks =
$event.fixHooks.touchstart =
$event.fixHooks.touchmove =
$event.fixHooks.touchend =
$event.fixHooks.touchcancel = {
props: "clientX clientY pageX pageY screenX screenY".split( " " ),
filter: function( event, orig ) {
if ( orig ){
var touched = ( orig.touches && orig.touches[0] )
|| ( orig.changedTouches && orig.changedTouches[0] )
|| null;
// iOS webkit: touchstart, touchmove, touchend
if ( touched )
$.each( touchHooks.props, function( i, prop ){
event[ prop ] = touched[ prop ];
});
}
return event;
}
};
// share the same special event configuration with related events...
$special.draginit = $special.dragstart = $special.dragend = drag;
})( jQuery );