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07-event.js

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Events

var rnamespaces = /\.(.*)$/,
  rformElems = /^(?:textarea|input|select)$/i,
  rperiod = /\./g,
  rspaces = / /g,
  rescape = /[^\w\s.|`]/g,
  fcleanup = function( nm ) {
    return nm.replace(rescape, "\\$&");
  };

A number of helper functions used for managing events. Many of the ideas behind this code originated from Dean Edwards' addEvent library.

jQuery.event = {

Bind an event to an element Original by Dean Edwards

  add: function( elem, types, handler, data ) {
    if ( elem.nodeType === 3 || elem.nodeType === 8 ) {
      return;
    }

    if ( handler === false ) {
      handler = returnFalse;
    } else if ( !handler ) {

Fixes bug #7229. Fix recommended by jdalton

      return;
    }

    var handleObjIn, handleObj;

    if ( handler.handler ) {
      handleObjIn = handler;
      handler = handleObjIn.handler;
    }

Make sure that the function being executed has a unique ID

    if ( !handler.guid ) {
      handler.guid = jQuery.guid++;
    }

Init the element's event structure

    var elemData = jQuery._data( elem );

If no elemData is found then we must be trying to bind to one of the banned noData elements

    if ( !elemData ) {
      return;
    }

    var events = elemData.events,
      eventHandle = elemData.handle;

    if ( !events ) {
      elemData.events = events = {};
    }

    if ( !eventHandle ) {
      elemData.handle = eventHandle = function( e ) {

Discard the second event of a jQuery.event.trigger() and when an event is called after a page has unloaded

        return typeof jQuery !== "undefined" && (!e || jQuery.event.triggered !== e.type) ?
          jQuery.event.handle.apply( eventHandle.elem, arguments ) :
          undefined;
      };
    }

Add elem as a property of the handle function This is to prevent a memory leak with non-native events in IE.

    eventHandle.elem = elem;

Handle multiple events separated by a space jQuery(...).bind("mouseover mouseout", fn);

    types = types.split(" ");

    var type, i = 0, namespaces;

    while ( (type = types[ i++ ]) ) {
      handleObj = handleObjIn ?
        jQuery.extend({}, handleObjIn) :
        { handler: handler, data: data };

Namespaced event handlers

      if ( type.indexOf(".") > -1 ) {
        namespaces = type.split(".");
        type = namespaces.shift();
        handleObj.namespace = namespaces.slice(0).sort().join(".");

      } else {
        namespaces = [];
        handleObj.namespace = "";
      }

      handleObj.type = type;
      if ( !handleObj.guid ) {
        handleObj.guid = handler.guid;
      }

Get the current list of functions bound to this event

      var handlers = events[ type ],
        special = jQuery.event.special[ type ] || {};

Init the event handler queue

      if ( !handlers ) {
        handlers = events[ type ] = [];

Check for a special event handler Only use addEventListener/attachEvent if the special events handler returns false

        if ( !special.setup || special.setup.call( elem, data, namespaces, eventHandle ) === false ) {

Bind the global event handler to the element

          if ( elem.addEventListener ) {
            elem.addEventListener( type, eventHandle, false );

          } else if ( elem.attachEvent ) {
            elem.attachEvent( "on" + type, eventHandle );
          }
        }
      }

      if ( special.add ) {
        special.add.call( elem, handleObj );

        if ( !handleObj.handler.guid ) {
          handleObj.handler.guid = handler.guid;
        }
      }

Add the function to the element's handler list

      handlers.push( handleObj );

Keep track of which events have been used, for event optimization

      jQuery.event.global[ type ] = true;
    }

Nullify elem to prevent memory leaks in IE

    elem = null;
  },

  global: {},

Detach an event or set of events from an element

  remove: function( elem, types, handler, pos ) {

don't do events on text and comment nodes

    if ( elem.nodeType === 3 || elem.nodeType === 8 ) {
      return;
    }

    if ( handler === false ) {
      handler = returnFalse;
    }

    var ret, type, fn, j, i = 0, all, namespaces, namespace, special, eventType, handleObj, origType,
      elemData = jQuery.hasData( elem ) && jQuery._data( elem ),
      events = elemData && elemData.events;

    if ( !elemData || !events ) {
      return;
    }

types is actually an event object here

    if ( types && types.type ) {
      handler = types.handler;
      types = types.type;
    }

Unbind all events for the element

    if ( !types || typeof types === "string" && types.charAt(0) === "." ) {
      types = types || "";

      for ( type in events ) {
        jQuery.event.remove( elem, type + types );
      }

      return;
    }

Handle multiple events separated by a space jQuery(...).unbind("mouseover mouseout", fn);

    types = types.split(" ");

    while ( (type = types[ i++ ]) ) {
      origType = type;
      handleObj = null;
      all = type.indexOf(".") < 0;
      namespaces = [];

      if ( !all ) {

Namespaced event handlers

        namespaces = type.split(".");
        type = namespaces.shift();

        namespace = new RegExp("(^|\\.)" +
          jQuery.map( namespaces.slice(0).sort(), fcleanup ).join("\\.(?:.*\\.)?") + "(\\.|$)");
      }

      eventType = events[ type ];

      if ( !eventType ) {
        continue;
      }

      if ( !handler ) {
        for ( j = 0; j < eventType.length; j++ ) {
          handleObj = eventType[ j ];

          if ( all || namespace.test( handleObj.namespace ) ) {
            jQuery.event.remove( elem, origType, handleObj.handler, j );
            eventType.splice( j--, 1 );
          }
        }

        continue;
      }

      special = jQuery.event.special[ type ] || {};

      for ( j = pos || 0; j < eventType.length; j++ ) {
        handleObj = eventType[ j ];

        if ( handler.guid === handleObj.guid ) {

remove the given handler for the given type

          if ( all || namespace.test( handleObj.namespace ) ) {
            if ( pos == null ) {
              eventType.splice( j--, 1 );
            }

            if ( special.remove ) {
              special.remove.call( elem, handleObj );
            }
          }

          if ( pos != null ) {
            break;
          }
        }
      }

remove generic event handler if no more handlers exist

      if ( eventType.length === 0 || pos != null && eventType.length === 1 ) {
        if ( !special.teardown || special.teardown.call( elem, namespaces ) === false ) {
          jQuery.removeEvent( elem, type, elemData.handle );
        }

        ret = null;
        delete events[ type ];
      }
    }

Remove the expando if it's no longer used

    if ( jQuery.isEmptyObject( events ) ) {
      var handle = elemData.handle;
      if ( handle ) {
        handle.elem = null;
      }

      delete elemData.events;
      delete elemData.handle;

      if ( jQuery.isEmptyObject( elemData ) ) {
        jQuery.removeData( elem, undefined, true );
      }
    }
  },
  

Events that are safe to short-circuit if no handlers are attached. Native DOM events should not be added, they may have inline handlers.

  customEvent: {
    "getData": true,
    "setData": true,
    "changeData": true
  },

  trigger: function( event, data, elem, onlyHandlers ) {

Event object or event type

    var type = event.type || event,
      namespaces = [],
      exclusive;

    if ( type.indexOf("!") >= 0 ) {

Exclusive events trigger only for the exact event (no namespaces)

      type = type.slice(0, -1);
      exclusive = true;
    }

    if ( type.indexOf(".") >= 0 ) {

Namespaced trigger; create a regexp to match event type in handle()

      namespaces = type.split(".");
      type = namespaces.shift();
      namespaces.sort();
    }

    if ( (!elem || jQuery.event.customEvent[ type ]) && !jQuery.event.global[ type ] ) {

No jQuery handlers for this event type, and it can't have inline handlers

      return;
    }

Caller can pass in an Event, Object, or just an event type string

    event = typeof event === "object" ?

jQuery.Event object

      event[ jQuery.expando ] ? event :

Object literal

      new jQuery.Event( type, event ) :

Just the event type (string)

      new jQuery.Event( type );

    event.type = type;
    event.exclusive = exclusive;
    event.namespace = namespaces.join(".");
    event.namespace_re = new RegExp("(^|\\.)" + namespaces.join("\\.(?:.*\\.)?") + "(\\.|$)");
    

triggerHandler() and global events don't bubble or run the default action

    if ( onlyHandlers || !elem ) {
      event.preventDefault();
      event.stopPropagation();
    }

Handle a global trigger

    if ( !elem ) {

TODO: Stop taunting the data cache; remove global events and always attach to document

      jQuery.each( jQuery.cache, function() {

internalKey variable is just used to make it easier to find and potentially change this stuff later; currently it just points to jQuery.expando

        var internalKey = jQuery.expando,
          internalCache = this[ internalKey ];
        if ( internalCache && internalCache.events && internalCache.events[ type ] ) {
          jQuery.event.trigger( event, data, internalCache.handle.elem );
        }
      });
      return;
    }

Don't do events on text and comment nodes

    if ( elem.nodeType === 3 || elem.nodeType === 8 ) {
      return;
    }

Clean up the event in case it is being reused

    event.result = undefined;
    event.target = elem;

Clone any incoming data and prepend the event, creating the handler arg list

    data = data != null ? jQuery.makeArray( data ) : [];
    data.unshift( event );

    var cur = elem,

IE doesn't like method names with a colon (#3533, #8272)

      ontype = type.indexOf(":") < 0 ? "on" + type : "";

Fire event on the current element, then bubble up the DOM tree

    do {
      var handle = jQuery._data( cur, "handle" );

      event.currentTarget = cur;
      if ( handle ) {
        handle.apply( cur, data );
      }

Trigger an inline bound script

      if ( ontype && jQuery.acceptData( cur ) && cur[ ontype ] && cur[ ontype ].apply( cur, data ) === false ) {
        event.result = false;
        event.preventDefault();
      }

Bubble up to document, then to window

      cur = cur.parentNode || cur.ownerDocument || cur === event.target.ownerDocument && window;
    } while ( cur && !event.isPropagationStopped() );

If nobody prevented the default action, do it now

    if ( !event.isDefaultPrevented() ) {
      var old,
        special = jQuery.event.special[ type ] || {};

      if ( (!special._default || special._default.call( elem.ownerDocument, event ) === false) &&
        !(type === "click" && jQuery.nodeName( elem, "a" )) && jQuery.acceptData( elem ) ) {

Call a native DOM method on the target with the same name name as the event. Can't use an .isFunction)() check here because IE6/7 fails that test. IE<9 dies on focus to hidden element (#1486), may want to revisit a try/catch.

        try {
          if ( ontype && elem[ type ] ) {

Don't re-trigger an onFOO event when we call its FOO() method

            old = elem[ ontype ];

            if ( old ) {
              elem[ ontype ] = null;
            }

            jQuery.event.triggered = type;
            elem[ type ]();
          }
        } catch ( ieError ) {}

        if ( old ) {
          elem[ ontype ] = old;
        }

        jQuery.event.triggered = undefined;
      }
    }
    
    return event.result;
  },

  handle: function( event ) {
    event = jQuery.event.fix( event || window.event );

Snapshot the handlers list since a called handler may add/remove events.

    var handlers = ((jQuery._data( this, "events" ) || {})[ event.type ] || []).slice(0),
      run_all = !event.exclusive && !event.namespace,
      args = Array.prototype.slice.call( arguments, 0 );

Use the fix-ed Event rather than the (read-only) native event

    args[0] = event;
    event.currentTarget = this;

    for ( var j = 0, l = handlers.length; j < l; j++ ) {
      var handleObj = handlers[ j ];

Triggered event must 1) be non-exclusive and have no namespace, or 2) have namespace(s) a subset or equal to those in the bound event.

      if ( run_all || event.namespace_re.test( handleObj.namespace ) ) {

Pass in a reference to the handler function itself So that we can later remove it

        event.handler = handleObj.handler;
        event.data = handleObj.data;
        event.handleObj = handleObj;

        var ret = handleObj.handler.apply( this, args );

        if ( ret !== undefined ) {
          event.result = ret;
          if ( ret === false ) {
            event.preventDefault();
            event.stopPropagation();
          }
        }

        if ( event.isImmediatePropagationStopped() ) {
          break;
        }
      }
    }
    return event.result;
  },

  props: "altKey attrChange attrName bubbles button cancelable charCode clientX clientY ctrlKey currentTarget data detail eventPhase fromElement handler keyCode layerX layerY metaKey newValue offsetX offsetY pageX pageY prevValue relatedNode relatedTarget screenX screenY shiftKey srcElement target toElement view wheelDelta which".split(" "),

  fix: function( event ) {
    if ( event[ jQuery.expando ] ) {
      return event;
    }

store a copy of the original event object and "clone" to set read-only properties

    var originalEvent = event;
    event = jQuery.Event( originalEvent );

    for ( var i = this.props.length, prop; i; ) {
      prop = this.props[ --i ];
      event[ prop ] = originalEvent[ prop ];
    }

Fix target property, if necessary

    if ( !event.target ) {

Fixes #1925 where srcElement might not be defined either

      event.target = event.srcElement || document;
    }

check if target is a textnode (safari)

    if ( event.target.nodeType === 3 ) {
      event.target = event.target.parentNode;
    }

Add relatedTarget, if necessary

    if ( !event.relatedTarget && event.fromElement ) {
      event.relatedTarget = event.fromElement === event.target ? event.toElement : event.fromElement;
    }

Calculate pageX/Y if missing and clientX/Y available

    if ( event.pageX == null && event.clientX != null ) {
      var eventDocument = event.target.ownerDocument || document,
        doc = eventDocument.documentElement,
        body = eventDocument.body;

      event.pageX = event.clientX + (doc && doc.scrollLeft || body && body.scrollLeft || 0) - (doc && doc.clientLeft || body && body.clientLeft || 0);
      event.pageY = event.clientY + (doc && doc.scrollTop  || body && body.scrollTop  || 0) - (doc && doc.clientTop  || body && body.clientTop  || 0);
    }

Add which for key events

    if ( event.which == null && (event.charCode != null || event.keyCode != null) ) {
      event.which = event.charCode != null ? event.charCode : event.keyCode;
    }

Add metaKey to non-Mac browsers (use ctrl for PC's and Meta for Macs)

    if ( !event.metaKey && event.ctrlKey ) {
      event.metaKey = event.ctrlKey;
    }

Add which for click: 1 === left; 2 === middle; 3 === right Note: button is not normalized, so don't use it

    if ( !event.which && event.button !== undefined ) {
      event.which = (event.button & 1 ? 1 : ( event.button & 2 ? 3 : ( event.button & 4 ? 2 : 0 ) ));
    }

    return event;
  },

Deprecated, use jQuery.guid instead

  guid: 1E8,

Deprecated, use jQuery.proxy instead

  proxy: jQuery.proxy,

  special: {
    ready: {

Make sure the ready event is setup

      setup: jQuery.bindReady,
      teardown: jQuery.noop
    },

    live: {
      add: function( handleObj ) {
        jQuery.event.add( this,
          liveConvert( handleObj.origType, handleObj.selector ),
          jQuery.extend({}, handleObj, {handler: liveHandler, guid: handleObj.handler.guid}) );
      },

      remove: function( handleObj ) {
        jQuery.event.remove( this, liveConvert( handleObj.origType, handleObj.selector ), handleObj );
      }
    },

    beforeunload: {
      setup: function( data, namespaces, eventHandle ) {

We only want to do this special case on windows

        if ( jQuery.isWindow( this ) ) {
          this.onbeforeunload = eventHandle;
        }
      },

      teardown: function( namespaces, eventHandle ) {
        if ( this.onbeforeunload === eventHandle ) {
          this.onbeforeunload = null;
        }
      }
    }
  }
};

jQuery.removeEvent = document.removeEventListener ?
  function( elem, type, handle ) {
    if ( elem.removeEventListener ) {
      elem.removeEventListener( type, handle, false );
    }
  } :
  function( elem, type, handle ) {
    if ( elem.detachEvent ) {
      elem.detachEvent( "on" + type, handle );
    }
  };

jQuery.Event = function( src, props ) {

Allow instantiation without the 'new' keyword

  if ( !this.preventDefault ) {
    return new jQuery.Event( src, props );
  }

Event object

  if ( src && src.type ) {
    this.originalEvent = src;
    this.type = src.type;

Events bubbling up the document may have been marked as prevented by a handler lower down the tree; reflect the correct value.

    this.isDefaultPrevented = (src.defaultPrevented || src.returnValue === false ||
      src.getPreventDefault && src.getPreventDefault()) ? returnTrue : returnFalse;

Event type

  } else {
    this.type = src;
  }

Put explicitly provided properties onto the event object

  if ( props ) {
    jQuery.extend( this, props );
  }

timeStamp is buggy for some events on Firefox(#3843) So we won't rely on the native value

  this.timeStamp = jQuery.now();

Mark it as fixed

  this[ jQuery.expando ] = true;
};

function returnFalse() {
  return false;
}
function returnTrue() {
  return true;
}

jQuery.Event is based on DOM3 Events as specified by the ECMAScript Language Binding http://www.w3.org/TR/2003/WD-DOM-Level-3-Events-20030331/ecma-script-binding.html

jQuery.Event.prototype = {
  preventDefault: function() {
    this.isDefaultPrevented = returnTrue;

    var e = this.originalEvent;
    if ( !e ) {
      return;
    }

if preventDefault exists run it on the original event

    if ( e.preventDefault ) {
      e.preventDefault();

otherwise set the returnValue property of the original event to false (IE)

    } else {
      e.returnValue = false;
    }
  },
  stopPropagation: function() {
    this.isPropagationStopped = returnTrue;

    var e = this.originalEvent;
    if ( !e ) {
      return;
    }

if stopPropagation exists run it on the original event

    if ( e.stopPropagation ) {
      e.stopPropagation();
    }

otherwise set the cancelBubble property of the original event to true (IE)

    e.cancelBubble = true;
  },
  stopImmediatePropagation: function() {
    this.isImmediatePropagationStopped = returnTrue;
    this.stopPropagation();
  },
  isDefaultPrevented: returnFalse,
  isPropagationStopped: returnFalse,
  isImmediatePropagationStopped: returnFalse
};

Checks if an event happened on an element within another element Used in jQuery.event.special.mouseenter and mouseleave handlers

var withinElement = function( event ) {

Check if mouse(over|out) are still within the same parent element

  var related = event.relatedTarget,
    inside = false,
    eventType = event.type;

  event.type = event.data;

  if ( related !== this ) {

    if ( related ) {
      inside = jQuery.contains( this, related );
    }

    if ( !inside ) {

      jQuery.event.handle.apply( this, arguments );

      event.type = eventType;
    }
  }
},

In case of event delegation, we only need to rename the event.type, liveHandler will take care of the rest.

delegate = function( event ) {
  event.type = event.data;
  jQuery.event.handle.apply( this, arguments );
};

Create mouseenter and mouseleave events

jQuery.each({
  mouseenter: "mouseover",
  mouseleave: "mouseout"
}, function( orig, fix ) {
  jQuery.event.special[ orig ] = {
    setup: function( data ) {
      jQuery.event.add( this, fix, data && data.selector ? delegate : withinElement, orig );
    },
    teardown: function( data ) {
      jQuery.event.remove( this, fix, data && data.selector ? delegate : withinElement );
    }
  };
});

submit delegation

if ( !jQuery.support.submitBubbles ) {

  jQuery.event.special.submit = {
    setup: function( data, namespaces ) {
      if ( !jQuery.nodeName( this, "form" ) ) {
        jQuery.event.add(this, "click.specialSubmit", function( e ) {
          var elem = e.target,
            type = elem.type;

          if ( (type === "submit" || type === "image") && jQuery( elem ).closest("form").length ) {
            trigger( "submit", this, arguments );
          }
        });

        jQuery.event.add(this, "keypress.specialSubmit", function( e ) {
          var elem = e.target,
            type = elem.type;

          if ( (type === "text" || type === "password") && jQuery( elem ).closest("form").length && e.keyCode === 13 ) {
            trigger( "submit", this, arguments );
          }
        });

      } else {
        return false;
      }
    },

    teardown: function( namespaces ) {
      jQuery.event.remove( this, ".specialSubmit" );
    }
  };

}

change delegation, happens here so we have bind.

if ( !jQuery.support.changeBubbles ) {

  var changeFilters,

  getVal = function( elem ) {
    var type = elem.type, val = elem.value;

    if ( type === "radio" || type === "checkbox" ) {
      val = elem.checked;

    } else if ( type === "select-multiple" ) {
      val = elem.selectedIndex > -1 ?
        jQuery.map( elem.options, function( elem ) {
          return elem.selected;
        }).join("-") :
        "";

    } else if ( jQuery.nodeName( elem, "select" ) ) {
      val = elem.selectedIndex;
    }

    return val;
  },

  testChange = function testChange( e ) {
    var elem = e.target, data, val;

    if ( !rformElems.test( elem.nodeName ) || elem.readOnly ) {
      return;
    }

    data = jQuery._data( elem, "_change_data" );
    val = getVal(elem);

the current data will be also retrieved by beforeactivate

    if ( e.type !== "focusout" || elem.type !== "radio" ) {
      jQuery._data( elem, "_change_data", val );
    }

    if ( data === undefined || val === data ) {
      return;
    }

    if ( data != null || val ) {
      e.type = "change";
      e.liveFired = undefined;
      jQuery.event.trigger( e, arguments[1], elem );
    }
  };

  jQuery.event.special.change = {
    filters: {
      focusout: testChange,

      beforedeactivate: testChange,

      click: function( e ) {
        var elem = e.target, type = jQuery.nodeName( elem, "input" ) ? elem.type : "";

        if ( type === "radio" || type === "checkbox" || jQuery.nodeName( elem, "select" ) ) {
          testChange.call( this, e );
        }
      },

Change has to be called before submit Keydown will be called before keypress, which is used in submit-event delegation

      keydown: function( e ) {
        var elem = e.target, type = jQuery.nodeName( elem, "input" ) ? elem.type : "";

        if ( (e.keyCode === 13 && !jQuery.nodeName( elem, "textarea" ) ) ||
          (e.keyCode === 32 && (type === "checkbox" || type === "radio")) ||
          type === "select-multiple" ) {
          testChange.call( this, e );
        }
      },

Beforeactivate happens also before the previous element is blurred with this event you can't trigger a change event, but you can store information

      beforeactivate: function( e ) {
        var elem = e.target;
        jQuery._data( elem, "_change_data", getVal(elem) );
      }
    },

    setup: function( data, namespaces ) {
      if ( this.type === "file" ) {
        return false;
      }

      for ( var type in changeFilters ) {
        jQuery.event.add( this, type + ".specialChange", changeFilters[type] );
      }

      return rformElems.test( this.nodeName );
    },

    teardown: function( namespaces ) {
      jQuery.event.remove( this, ".specialChange" );

      return rformElems.test( this.nodeName );
    }
  };

  changeFilters = jQuery.event.special.change.filters;

Handle when the input is .focus()'d

  changeFilters.focus = changeFilters.beforeactivate;
}

function trigger( type, elem, args ) {

Piggyback on a donor event to simulate a different one. Fake originalEvent to avoid donor's stopPropagation, but if the simulated event prevents default then we do the same on the donor. Don't pass args or remember liveFired; they apply to the donor event.

  var event = jQuery.extend( {}, args[ 0 ] );
  event.type = type;
  event.originalEvent = {};
  event.liveFired = undefined;
  jQuery.event.handle.call( elem, event );
  if ( event.isDefaultPrevented() ) {
    args[ 0 ].preventDefault();
  }
}

Create "bubbling" focus and blur events

if ( !jQuery.support.focusinBubbles ) {
  jQuery.each({ focus: "focusin", blur: "focusout" }, function( orig, fix ) {

Attach a single capturing handler while someone wants focusin/focusout

    var attaches = 0;

    jQuery.event.special[ fix ] = {
      setup: function() {
        if ( attaches++ === 0 ) {
          document.addEventListener( orig, handler, true );
        }
      },
      teardown: function() {
        if ( --attaches === 0 ) {
          document.removeEventListener( orig, handler, true );
        }
      }
    };

    function handler( donor ) {

Donor event is always a native one; fix it and switch its type. Let focusin/out handler cancel the donor focus/blur event.

      var e = jQuery.event.fix( donor );
      e.type = fix;
      e.originalEvent = {};
      jQuery.event.trigger( e, null, e.target );
      if ( e.isDefaultPrevented() ) {
        donor.preventDefault();
      }
    }
  });
}

jQuery.each(["bind", "one"], function( i, name ) {
  jQuery.fn[ name ] = function( type, data, fn ) {
    var handler;

Handle object literals

    if ( typeof type === "object" ) {
      for ( var key in type ) {
        this[ name ](key, data, type[key], fn);
      }
      return this;
    }

    if ( arguments.length === 2 || data === false ) {
      fn = data;
      data = undefined;
    }

    if ( name === "one" ) {
      handler = function( event ) {
        jQuery( this ).unbind( event, handler );
        return fn.apply( this, arguments );
      };
      handler.guid = fn.guid || jQuery.guid++;
    } else {
      handler = fn;
    }

    if ( type === "unload" && name !== "one" ) {
      this.one( type, data, fn );

    } else {
      for ( var i = 0, l = this.length; i < l; i++ ) {
        jQuery.event.add( this[i], type, handler, data );
      }
    }

    return this;
  };
});

jQuery.fn.extend({
  unbind: function( type, fn ) {

Handle object literals

    if ( typeof type === "object" && !type.preventDefault ) {
      for ( var key in type ) {
        this.unbind(key, type[key]);
      }

    } else {
      for ( var i = 0, l = this.length; i < l; i++ ) {
        jQuery.event.remove( this[i], type, fn );
      }
    }

    return this;
  },

  delegate: function( selector, types, data, fn ) {
    return this.live( types, data, fn, selector );
  },

  undelegate: function( selector, types, fn ) {
    if ( arguments.length === 0 ) {
      return this.unbind( "live" );

    } else {
      return this.die( types, null, fn, selector );
    }
  },

  trigger: function( type, data ) {
    return this.each(function() {
      jQuery.event.trigger( type, data, this );
    });
  },

  triggerHandler: function( type, data ) {
    if ( this[0] ) {
      return jQuery.event.trigger( type, data, this[0], true );
    }
  },

  toggle: function( fn ) {

Save reference to arguments for access in closure

    var args = arguments,
      guid = fn.guid || jQuery.guid++,
      i = 0,
      toggler = function( event ) {

Figure out which function to execute

        var lastToggle = ( jQuery.data( this, "lastToggle" + fn.guid ) || 0 ) % i;
        jQuery.data( this, "lastToggle" + fn.guid, lastToggle + 1 );

Make sure that clicks stop

        event.preventDefault();

and execute the function

        return args[ lastToggle ].apply( this, arguments ) || false;
      };

link all the functions, so any of them can unbind this click handler

    toggler.guid = guid;
    while ( i < args.length ) {
      args[ i++ ].guid = guid;
    }

    return this.click( toggler );
  },

  hover: function( fnOver, fnOut ) {
    return this.mouseenter( fnOver ).mouseleave( fnOut || fnOver );
  }
});

var liveMap = {
  focus: "focusin",
  blur: "focusout",
  mouseenter: "mouseover",
  mouseleave: "mouseout"
};

jQuery.each(["live", "die"], function( i, name ) {
  jQuery.fn[ name ] = function( types, data, fn, origSelector /* Internal Use Only */ ) {
    var type, i = 0, match, namespaces, preType,
      selector = origSelector || this.selector,
      context = origSelector ? this : jQuery( this.context );

    if ( typeof types === "object" && !types.preventDefault ) {
      for ( var key in types ) {
        context[ name ]( key, data, types[key], selector );
      }

      return this;
    }

    if ( name === "die" && !types &&
          origSelector && origSelector.charAt(0) === "." ) {

      context.unbind( origSelector );

      return this;
    }

    if ( data === false || jQuery.isFunction( data ) ) {
      fn = data || returnFalse;
      data = undefined;
    }

    types = (types || "").split(" ");

    while ( (type = types[ i++ ]) != null ) {
      match = rnamespaces.exec( type );
      namespaces = "";

      if ( match )  {
        namespaces = match[0];
        type = type.replace( rnamespaces, "" );
      }

      if ( type === "hover" ) {
        types.push( "mouseenter" + namespaces, "mouseleave" + namespaces );
        continue;
      }

      preType = type;

      if ( liveMap[ type ] ) {
        types.push( liveMap[ type ] + namespaces );
        type = type + namespaces;

      } else {
        type = (liveMap[ type ] || type) + namespaces;
      }

      if ( name === "live" ) {

bind live handler

        for ( var j = 0, l = context.length; j < l; j++ ) {
          jQuery.event.add( context[j], "live." + liveConvert( type, selector ),
            { data: data, selector: selector, handler: fn, origType: type, origHandler: fn, preType: preType } );
        }

      } else {

unbind live handler

        context.unbind( "live." + liveConvert( type, selector ), fn );
      }
    }

    return this;
  };
});

function liveHandler( event ) {
  var stop, maxLevel, related, match, handleObj, elem, j, i, l, data, close, namespace, ret,
    elems = [],
    selectors = [],
    events = jQuery._data( this, "events" );

Make sure we avoid non-left-click bubbling in Firefox (#3861) and disabled elements in IE (#6911)

  if ( event.liveFired === this || !events || !events.live || event.target.disabled || event.button && event.type === "click" ) {
    return;
  }

  if ( event.namespace ) {
    namespace = new RegExp("(^|\\.)" + event.namespace.split(".").join("\\.(?:.*\\.)?") + "(\\.|$)");
  }

  event.liveFired = this;

  var live = events.live.slice(0);

  for ( j = 0; j < live.length; j++ ) {
    handleObj = live[j];

    if ( handleObj.origType.replace( rnamespaces, "" ) === event.type ) {
      selectors.push( handleObj.selector );

    } else {
      live.splice( j--, 1 );
    }
  }

  match = jQuery( event.target ).closest( selectors, event.currentTarget );

  for ( i = 0, l = match.length; i < l; i++ ) {
    close = match[i];

    for ( j = 0; j < live.length; j++ ) {
      handleObj = live[j];

      if ( close.selector === handleObj.selector && (!namespace || namespace.test( handleObj.namespace )) && !close.elem.disabled ) {
        elem = close.elem;
        related = null;

Those two events require additional checking

        if ( handleObj.preType === "mouseenter" || handleObj.preType === "mouseleave" ) {
          event.type = handleObj.preType;
          related = jQuery( event.relatedTarget ).closest( handleObj.selector )[0];

Make sure not to accidentally match a child element with the same selector

          if ( related && jQuery.contains( elem, related ) ) {
            related = elem;
          }
        }

        if ( !related || related !== elem ) {
          elems.push({ elem: elem, handleObj: handleObj, level: close.level });
        }
      }
    }
  }

  for ( i = 0, l = elems.length; i < l; i++ ) {
    match = elems[i];

    if ( maxLevel && match.level > maxLevel ) {
      break;
    }

    event.currentTarget = match.elem;
    event.data = match.handleObj.data;
    event.handleObj = match.handleObj;

    ret = match.handleObj.origHandler.apply( match.elem, arguments );

    if ( ret === false || event.isPropagationStopped() ) {
      maxLevel = match.level;

      if ( ret === false ) {
        stop = false;
      }
      if ( event.isImmediatePropagationStopped() ) {
        break;
      }
    }
  }

  return stop;
}

function liveConvert( type, selector ) {
  return (type && type !== "*" ? type + "." : "") + selector.replace(rperiod, "`").replace(rspaces, "&");
}

jQuery.each( ("blur focus focusin focusout load resize scroll unload click dblclick " +
  "mousedown mouseup mousemove mouseover mouseout mouseenter mouseleave " +
  "change select submit keydown keypress keyup error").split(" "), function( i, name ) {

Handle event binding

  jQuery.fn[ name ] = function( data, fn ) {
    if ( fn == null ) {
      fn = data;
      data = null;
    }

    return arguments.length > 0 ?
      this.bind( name, data, fn ) :
      this.trigger( name );
  };

  if ( jQuery.attrFn ) {
    jQuery.attrFn[ name ] = true;
  }
});