1 | /*!
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2 | jquery.event.drag.js ~ v1.4 ~ Copyright (c) 2008, Three Dub Media (http://threedubmedia.com)
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3 | Liscensed under the MIT License ~ http://threedubmedia.googlecode.com/files/MIT-LICENSE.txt
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4 | */
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5 | ;(function($){ // secure $ jQuery alias
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6 | /*******************************************************************************************/
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7 | // Created: 2008-06-04 | Updated: 2009-01-26
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8 | /*******************************************************************************************/
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9 | // Events: drag, dragstart, dragend
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10 | /*******************************************************************************************/
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11 |
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12 | // jquery method
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13 | $.fn.drag = function( fn1, fn2, fn3 ){
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14 | if ( fn2 ) this.bind('dragstart', fn1 ); // 2+ args
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15 | if ( fn3 ) this.bind('dragend', fn3 ); // 3 args
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16 | return !fn1 ? this.trigger('drag') // 0 args
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17 | : this.bind('drag', fn2 ? fn2 : fn1 ); // 1+ args
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18 | };
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19 |
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20 | // local refs
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21 | var $event = $.event, $special = $event.special,
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22 |
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23 | // special event configuration
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24 | drag = $special.drag = {
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25 | not: ':input', // don't begin to drag on event.targets that match this selector
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26 | distance: 0, // distance dragged before dragstart
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27 | which: 1, // mouse button pressed to start drag sequence
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28 | setup: function( data ){
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29 | data = $.extend({
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30 | distance: drag.distance,
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31 | which: drag.which,
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32 | not: drag.not
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33 | }, data || {});
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34 | data.distance = squared( data.distance ); // xイ + yイ = distanceイ
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35 | $event.add( this, "mousedown", handler, data );
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36 | },
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37 | teardown: function(){
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38 | $event.remove( this, "mousedown", handler );
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39 | if ( this === drag.dragging ) drag.dragging = drag.proxy = null; // deactivate element
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40 | selectable( this, true ); // enable text selection
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41 | }
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42 | };
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43 |
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44 | // handle drag-releatd DOM events
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45 | function handler ( event ){
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46 | var elem = this, returned, data = event.data || {};
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47 | // mousemove or mouseup
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48 | if ( data.elem ){
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49 | // update event properties...
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50 | elem = event.dragTarget = data.elem; // drag source element
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51 | event.dragProxy = drag.proxy || elem; // proxy element or source
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52 | event.cursorOffsetX = data.pageX - data.left; // mousedown offset
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53 | event.cursorOffsetY = data.pageY - data.top; // mousedown offset
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54 | event.offsetX = event.pageX - event.cursorOffsetX; // element offset
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55 | event.offsetY = event.pageY - event.cursorOffsetY; // element offset
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56 | }
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57 | // mousedown, check some initial props to avoid the switch statement
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58 | else if ( drag.dragging || ( data.which>0 && event.which!=data.which ) ||
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59 | $( event.target ).is( data.not ) ) return;
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60 | // handle various events
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61 | switch ( event.type ){
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62 | // mousedown, left click, event.target is not restricted, init dragging
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63 | case 'mousedown':
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64 | $.extend( data, $( elem ).offset(), {
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65 | elem: elem, target: event.target,
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66 | pageX: event.pageX, pageY: event.pageY
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67 | }); // store some initial attributes
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68 | $event.add( document, "mousemove mouseup", handler, data );
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69 | selectable( elem, false ); // disable text selection
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70 | return false; // prevents text selection in safari
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71 | // mousemove, check distance, start dragging
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72 | case !drag.dragging && 'mousemove':
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73 | if ( squared( event.pageX-data.pageX )
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74 | + squared( event.pageY-data.pageY ) // xイ + yイ = distanceイ
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75 | < data.distance ) break; // distance tolerance not reached
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76 | event.target = data.target; // force target from "mousedown" event (fix distance issue)
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77 | returned = hijack( event, "dragstart", elem ); // trigger "dragstart", return proxy element
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78 | if ( returned !== false ){ // "dragstart" not rejected
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79 | drag.dragging = elem; // activate element
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80 | drag.proxy = event.dragProxy = $( returned || elem )[0]; // set proxy
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81 | }
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82 | // mousemove, dragging
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83 | case 'mousemove':
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84 | if ( drag.dragging ){
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85 | returned = hijack( event, "drag", elem ); // trigger "drag"
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86 | if ( $special.drop ){ // manage drop events
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87 | $special.drop.allowed = ( returned !== false ); // prevent drop
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88 | $special.drop.handler( event ); // "dropstart", "dropend"
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89 | }
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90 | if ( returned !== false ) break; // "drag" not rejected, stop
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91 | event.type = "mouseup"; // helps "drop" handler behave
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92 | }
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93 | // mouseup, stop dragging
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94 | case 'mouseup':
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95 | $event.remove( document, "mousemove mouseup", handler ); // remove page events
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96 | if ( drag.dragging ) {
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97 | if ( $special.drop ) $special.drop.handler( event ); // "drop"
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98 | hijack( event, "dragend", elem ); // trigger "dragend"
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99 | } else {
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100 | hijack( event, "dragclickonly", elem );
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101 | }
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102 | selectable( elem, true ); // enable text selection
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103 | drag.dragging = drag.proxy = data.elem = null; // deactivate element
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104 | break;
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105 | }
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106 | };
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107 |
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108 | // set event type to custom value, and handle it
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109 | function hijack ( event, type, elem ){
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110 | event.type = type; // force the event type
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111 | var result = $event.handle.call( elem, event );
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112 | return result===false ? false : result || event.result;
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113 | };
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114 |
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115 | // return the value squared
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116 | function squared ( value ){ return Math.pow( value, 2 ); };
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117 |
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118 | // toggles text selection attributes
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119 | function selectable ( elem, bool ){
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120 | if ( !elem ) return; // maybe element was removed ?
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121 | elem.unselectable = bool ? "off" : "on"; // IE
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122 | elem.onselectstart = function(){ return bool; }; // IE
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123 | if ( document.selection && document.selection.empty ) document.selection.empty(); // IE
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124 | if ( elem.style ) elem.style.MozUserSelect = bool ? "" : "none"; // FF
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125 | };
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126 |
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127 | /*******************************************************************************************/
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128 | })( jQuery ); // confine scope |
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