www.gusucode.com > 一个基于extjs的强大聊天插件源码程序 > 一个基于extjs的强大聊天插件/extjame/ext-jame/js/ext2/source/dd/DropZone.js
/*
* Ext JS Library 2.0.2
* Copyright(c) 2006-2008, Ext JS, LLC.
* licensing@extjs.com
*
* http://extjs.com/license
*/
/**
* @class Ext.dd.DropZone
* @extends Ext.dd.DropTarget
* This class provides a container DD instance that proxies for multiple child node targets.<br />
* By default, this class requires that child nodes accepting drop are registered with {@link Ext.dd.Registry}.
* @constructor
* @param {Mixed} el The container element
* @param {Object} config
*/
Ext.dd.DropZone = function(el, config){
Ext.dd.DropZone.superclass.constructor.call(this, el, config);
};
Ext.extend(Ext.dd.DropZone, Ext.dd.DropTarget, {
/**
* Returns a custom data object associated with the DOM node that is the target of the event. By default
* this looks up the event target in the {@link Ext.dd.Registry}, although you can override this method to
* provide your own custom lookup.
* @param {Event} e The event
* @return {Object} data The custom data
*/
getTargetFromEvent : function(e){
return Ext.dd.Registry.getTargetFromEvent(e);
},
/**
* Called internally when the DropZone determines that a {@link Ext.dd.DragSource} has entered a drop node
* that it has registered. This method has no default implementation and should be overridden to provide
* node-specific processing if necessary.
* @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
* {@link #getTargetFromEvent} for this node)
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
*/
onNodeEnter : function(n, dd, e, data){
},
/**
* Called internally while the DropZone determines that a {@link Ext.dd.DragSource} is over a drop node
* that it has registered. The default implementation returns this.dropNotAllowed, so it should be
* overridden to provide the proper feedback.
* @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
* {@link #getTargetFromEvent} for this node)
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {String} status The CSS class that communicates the drop status back to the source so that the
* underlying {@link Ext.dd.StatusProxy} can be updated
*/
onNodeOver : function(n, dd, e, data){
return this.dropAllowed;
},
/**
* Called internally when the DropZone determines that a {@link Ext.dd.DragSource} has been dragged out of
* the drop node without dropping. This method has no default implementation and should be overridden to provide
* node-specific processing if necessary.
* @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
* {@link #getTargetFromEvent} for this node)
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
*/
onNodeOut : function(n, dd, e, data){
},
/**
* Called internally when the DropZone determines that a {@link Ext.dd.DragSource} has been dropped onto
* the drop node. The default implementation returns false, so it should be overridden to provide the
* appropriate processing of the drop event and return true so that the drag source's repair action does not run.
* @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
* {@link #getTargetFromEvent} for this node)
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {Boolean} True if the drop was valid, else false
*/
onNodeDrop : function(n, dd, e, data){
return false;
},
/**
* Called internally while the DropZone determines that a {@link Ext.dd.DragSource} is being dragged over it,
* but not over any of its registered drop nodes. The default implementation returns this.dropNotAllowed, so
* it should be overridden to provide the proper feedback if necessary.
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {String} status The CSS class that communicates the drop status back to the source so that the
* underlying {@link Ext.dd.StatusProxy} can be updated
*/
onContainerOver : function(dd, e, data){
return this.dropNotAllowed;
},
/**
* Called internally when the DropZone determines that a {@link Ext.dd.DragSource} has been dropped on it,
* but not on any of its registered drop nodes. The default implementation returns false, so it should be
* overridden to provide the appropriate processing of the drop event if you need the drop zone itself to
* be able to accept drops. It should return true when valid so that the drag source's repair action does not run.
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {Boolean} True if the drop was valid, else false
*/
onContainerDrop : function(dd, e, data){
return false;
},
/**
* The function a {@link Ext.dd.DragSource} calls once to notify this drop zone that the source is now over
* the zone. The default implementation returns this.dropNotAllowed and expects that only registered drop
* nodes can process drag drop operations, so if you need the drop zone itself to be able to process drops
* you should override this method and provide a custom implementation.
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {String} status The CSS class that communicates the drop status back to the source so that the
* underlying {@link Ext.dd.StatusProxy} can be updated
*/
notifyEnter : function(dd, e, data){
return this.dropNotAllowed;
},
/**
* The function a {@link Ext.dd.DragSource} calls continuously while it is being dragged over the drop zone.
* This method will be called on every mouse movement while the drag source is over the drop zone.
* It will call {@link #onNodeOver} while the drag source is over a registered node, and will also automatically
* delegate to the appropriate node-specific methods as necessary when the drag source enters and exits
* registered nodes ({@link #onNodeEnter}, {@link #onNodeOut}). If the drag source is not currently over a
* registered node, it will call {@link #onContainerOver}.
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {String} status The CSS class that communicates the drop status back to the source so that the
* underlying {@link Ext.dd.StatusProxy} can be updated
*/
notifyOver : function(dd, e, data){
var n = this.getTargetFromEvent(e);
if(!n){ // not over valid drop target
if(this.lastOverNode){
this.onNodeOut(this.lastOverNode, dd, e, data);
this.lastOverNode = null;
}
return this.onContainerOver(dd, e, data);
}
if(this.lastOverNode != n){
if(this.lastOverNode){
this.onNodeOut(this.lastOverNode, dd, e, data);
}
this.onNodeEnter(n, dd, e, data);
this.lastOverNode = n;
}
return this.onNodeOver(n, dd, e, data);
},
/**
* The function a {@link Ext.dd.DragSource} calls once to notify this drop zone that the source has been dragged
* out of the zone without dropping. If the drag source is currently over a registered node, the notification
* will be delegated to {@link #onNodeOut} for node-specific handling, otherwise it will be ignored.
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop target
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag zone
*/
notifyOut : function(dd, e, data){
if(this.lastOverNode){
this.onNodeOut(this.lastOverNode, dd, e, data);
this.lastOverNode = null;
}
},
/**
* The function a {@link Ext.dd.DragSource} calls once to notify this drop zone that the dragged item has
* been dropped on it. The drag zone will look up the target node based on the event passed in, and if there
* is a node registered for that event, it will delegate to {@link #onNodeDrop} for node-specific handling,
* otherwise it will call {@link #onContainerDrop}.
* @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
* @param {Event} e The event
* @param {Object} data An object containing arbitrary data supplied by the drag source
* @return {Boolean} True if the drop was valid, else false
*/
notifyDrop : function(dd, e, data){
if(this.lastOverNode){
this.onNodeOut(this.lastOverNode, dd, e, data);
this.lastOverNode = null;
}
var n = this.getTargetFromEvent(e);
return n ?
this.onNodeDrop(n, dd, e, data) :
this.onContainerDrop(dd, e, data);
},
// private
triggerCacheRefresh : function(){
Ext.dd.DDM.refreshCache(this.groups);
}
});