/hippo/src/main/webapp/ext/src/dd/DropZone.js

  1/*!
  2 * Ext JS Library 3.0.0
  3 * Copyright(c) 2006-2009 Ext JS, LLC
  4 * licensing@extjs.com
  5 * http://www.extjs.com/license
  6 */
  7/**
  8 * @class Ext.dd.DropZone
  9 * @extends Ext.dd.DropTarget
 10 * <p>This class provides a container DD instance that allows dropping on multiple child target nodes.</p>
 11 * <p>By default, this class requires that child nodes accepting drop are registered with {@link Ext.dd.Registry}.
 12 * However a simpler way to allow a DropZone to manage any number of target elements is to configure the
 13 * DropZone with an implementation of {@link #getTargetFromEvent} which interrogates the passed
 14 * mouse event to see if it has taken place within an element, or class of elements. This is easily done
 15 * by using the event's {@link Ext.EventObject#getTarget getTarget} method to identify a node based on a
 16 * {@link Ext.DomQuery} selector.</p>
 17 * <p>Once the DropZone has detected through calling getTargetFromEvent, that the mouse is over
 18 * a drop target, that target is passed as the first parameter to {@link #onNodeEnter}, {@link #onNodeOver},
 19 * {@link #onNodeOut}, {@link #onNodeDrop}. You may configure the instance of DropZone with implementations
 20 * of these methods to provide application-specific behaviour for these events to update both
 21 * application state, and UI state.</p>
 22 * <p>For example to make a GridPanel a cooperating target with the example illustrated in
 23 * {@link Ext.dd.DragZone DragZone}, the following technique might be used:</p><pre><code>
 24myGridPanel.on('render', function() {
 25    myGridPanel.dropZone = new Ext.dd.DropZone(myGridPanel.getView().scroller, {
 26
 27//      If the mouse is over a grid row, return that node. This is
 28//      provided as the "target" parameter in all "onNodeXXXX" node event handling functions
 29        getTargetFromEvent: function(e) {
 30            return e.getTarget(myGridPanel.getView().rowSelector);
 31        },
 32
 33//      On entry into a target node, highlight that node.
 34        onNodeEnter : function(target, dd, e, data){ 
 35            Ext.fly(target).addClass('my-row-highlight-class');
 36        },
 37
 38//      On exit from a target node, unhighlight that node.
 39        onNodeOut : function(target, dd, e, data){ 
 40            Ext.fly(target).removeClass('my-row-highlight-class');
 41        },
 42
 43//      While over a target node, return the default drop allowed class which
 44//      places a "tick" icon into the drag proxy.
 45        onNodeOver : function(target, dd, e, data){ 
 46            return Ext.dd.DropZone.prototype.dropAllowed;
 47        },
 48
 49//      On node drop we can interrogate the target to find the underlying
 50//      application object that is the real target of the dragged data.
 51//      In this case, it is a Record in the GridPanel's Store.
 52//      We can use the data set up by the DragZone's getDragData method to read
 53//      any data we decided to attach in the DragZone's getDragData method.
 54        onNodeDrop : function(target, dd, e, data){
 55            var rowIndex = myGridPanel.getView().findRowIndex(target);
 56            var r = myGridPanel.getStore().getAt(rowIndex);
 57            Ext.Msg.alert('Drop gesture', 'Dropped Record id ' + data.draggedRecord.id +
 58                ' on Record id ' + r.id);
 59            return true;
 60        }
 61    });
 62}
 63</code></pre>
 64 * See the {@link Ext.dd.DragZone DragZone} documentation for details about building a DragZone which
 65 * cooperates with this DropZone.
 66 * @constructor
 67 * @param {Mixed} el The container element
 68 * @param {Object} config
 69 */
 70Ext.dd.DropZone = function(el, config){
 71    Ext.dd.DropZone.superclass.constructor.call(this, el, config);
 72};
 73
 74Ext.extend(Ext.dd.DropZone, Ext.dd.DropTarget, {
 75    /**
 76     * Returns a custom data object associated with the DOM node that is the target of the event.  By default
 77     * this looks up the event target in the {@link Ext.dd.Registry}, although you can override this method to
 78     * provide your own custom lookup.
 79     * @param {Event} e The event
 80     * @return {Object} data The custom data
 81     */
 82    getTargetFromEvent : function(e){
 83        return Ext.dd.Registry.getTargetFromEvent(e);
 84    },
 85
 86    /**
 87     * Called when the DropZone determines that a {@link Ext.dd.DragSource} has entered a drop node
 88     * that has either been registered or detected by a configured implementation of {@link #getTargetFromEvent}.
 89     * This method has no default implementation and should be overridden to provide
 90     * node-specific processing if necessary.
 91     * @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from 
 92     * {@link #getTargetFromEvent} for this node)
 93     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
 94     * @param {Event} e The event
 95     * @param {Object} data An object containing arbitrary data supplied by the drag source
 96     */
 97    onNodeEnter : function(n, dd, e, data){
 98        
 99    },
100
101    /**
102     * Called while the DropZone determines that a {@link Ext.dd.DragSource} is over a drop node
103     * that has either been registered or detected by a configured implementation of {@link #getTargetFromEvent}.
104     * The default implementation returns this.dropNotAllowed, so it should be
105     * overridden to provide the proper feedback.
106     * @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
107     * {@link #getTargetFromEvent} for this node)
108     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
109     * @param {Event} e The event
110     * @param {Object} data An object containing arbitrary data supplied by the drag source
111     * @return {String} status The CSS class that communicates the drop status back to the source so that the
112     * underlying {@link Ext.dd.StatusProxy} can be updated
113     */
114    onNodeOver : function(n, dd, e, data){
115        return this.dropAllowed;
116    },
117
118    /**
119     * Called when the DropZone determines that a {@link Ext.dd.DragSource} has been dragged out of
120     * the drop node without dropping.  This method has no default implementation and should be overridden to provide
121     * node-specific processing if necessary.
122     * @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
123     * {@link #getTargetFromEvent} for this node)
124     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
125     * @param {Event} e The event
126     * @param {Object} data An object containing arbitrary data supplied by the drag source
127     */
128    onNodeOut : function(n, dd, e, data){
129        
130    },
131
132    /**
133     * Called when the DropZone determines that a {@link Ext.dd.DragSource} has been dropped onto
134     * the drop node.  The default implementation returns false, so it should be overridden to provide the
135     * appropriate processing of the drop event and return true so that the drag source's repair action does not run.
136     * @param {Object} nodeData The custom data associated with the drop node (this is the same value returned from
137     * {@link #getTargetFromEvent} for this node)
138     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
139     * @param {Event} e The event
140     * @param {Object} data An object containing arbitrary data supplied by the drag source
141     * @return {Boolean} True if the drop was valid, else false
142     */
143    onNodeDrop : function(n, dd, e, data){
144        return false;
145    },
146
147    /**
148     * Called while the DropZone determines that a {@link Ext.dd.DragSource} is being dragged over it,
149     * but not over any of its registered drop nodes.  The default implementation returns this.dropNotAllowed, so
150     * it should be overridden to provide the proper feedback if necessary.
151     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
152     * @param {Event} e The event
153     * @param {Object} data An object containing arbitrary data supplied by the drag source
154     * @return {String} status The CSS class that communicates the drop status back to the source so that the
155     * underlying {@link Ext.dd.StatusProxy} can be updated
156     */
157    onContainerOver : function(dd, e, data){
158        return this.dropNotAllowed;
159    },
160
161    /**
162     * Called when the DropZone determines that a {@link Ext.dd.DragSource} has been dropped on it,
163     * but not on any of its registered drop nodes.  The default implementation returns false, so it should be
164     * overridden to provide the appropriate processing of the drop event if you need the drop zone itself to
165     * be able to accept drops.  It should return true when valid so that the drag source's repair action does not run.
166     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
167     * @param {Event} e The event
168     * @param {Object} data An object containing arbitrary data supplied by the drag source
169     * @return {Boolean} True if the drop was valid, else false
170     */
171    onContainerDrop : function(dd, e, data){
172        return false;
173    },
174
175    /**
176     * The function a {@link Ext.dd.DragSource} calls once to notify this drop zone that the source is now over
177     * the zone.  The default implementation returns this.dropNotAllowed and expects that only registered drop
178     * nodes can process drag drop operations, so if you need the drop zone itself to be able to process drops
179     * you should override this method and provide a custom implementation.
180     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
181     * @param {Event} e The event
182     * @param {Object} data An object containing arbitrary data supplied by the drag source
183     * @return {String} status The CSS class that communicates the drop status back to the source so that the
184     * underlying {@link Ext.dd.StatusProxy} can be updated
185     */
186    notifyEnter : function(dd, e, data){
187        return this.dropNotAllowed;
188    },
189
190    /**
191     * The function a {@link Ext.dd.DragSource} calls continuously while it is being dragged over the drop zone.
192     * This method will be called on every mouse movement while the drag source is over the drop zone.
193     * It will call {@link #onNodeOver} while the drag source is over a registered node, and will also automatically
194     * delegate to the appropriate node-specific methods as necessary when the drag source enters and exits
195     * registered nodes ({@link #onNodeEnter}, {@link #onNodeOut}). If the drag source is not currently over a
196     * registered node, it will call {@link #onContainerOver}.
197     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
198     * @param {Event} e The event
199     * @param {Object} data An object containing arbitrary data supplied by the drag source
200     * @return {String} status The CSS class that communicates the drop status back to the source so that the
201     * underlying {@link Ext.dd.StatusProxy} can be updated
202     */
203    notifyOver : function(dd, e, data){
204        var n = this.getTargetFromEvent(e);
205        if(!n){ // not over valid drop target
206            if(this.lastOverNode){
207                this.onNodeOut(this.lastOverNode, dd, e, data);
208                this.lastOverNode = null;
209            }
210            return this.onContainerOver(dd, e, data);
211        }
212        if(this.lastOverNode != n){
213            if(this.lastOverNode){
214                this.onNodeOut(this.lastOverNode, dd, e, data);
215            }
216            this.onNodeEnter(n, dd, e, data);
217            this.lastOverNode = n;
218        }
219        return this.onNodeOver(n, dd, e, data);
220    },
221
222    /**
223     * The function a {@link Ext.dd.DragSource} calls once to notify this drop zone that the source has been dragged
224     * out of the zone without dropping.  If the drag source is currently over a registered node, the notification
225     * will be delegated to {@link #onNodeOut} for node-specific handling, otherwise it will be ignored.
226     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop target
227     * @param {Event} e The event
228     * @param {Object} data An object containing arbitrary data supplied by the drag zone
229     */
230    notifyOut : function(dd, e, data){
231        if(this.lastOverNode){
232            this.onNodeOut(this.lastOverNode, dd, e, data);
233            this.lastOverNode = null;
234        }
235    },
236
237    /**
238     * The function a {@link Ext.dd.DragSource} calls once to notify this drop zone that the dragged item has
239     * been dropped on it.  The drag zone will look up the target node based on the event passed in, and if there
240     * is a node registered for that event, it will delegate to {@link #onNodeDrop} for node-specific handling,
241     * otherwise it will call {@link #onContainerDrop}.
242     * @param {Ext.dd.DragSource} source The drag source that was dragged over this drop zone
243     * @param {Event} e The event
244     * @param {Object} data An object containing arbitrary data supplied by the drag source
245     * @return {Boolean} True if the drop was valid, else false
246     */
247    notifyDrop : function(dd, e, data){
248        if(this.lastOverNode){
249            this.onNodeOut(this.lastOverNode, dd, e, data);
250            this.lastOverNode = null;
251        }
252        var n = this.getTargetFromEvent(e);
253        return n ?
254            this.onNodeDrop(n, dd, e, data) :
255            this.onContainerDrop(dd, e, data);
256    },
257
258    // private
259    triggerCacheRefresh : function(){
260        Ext.dd.DDM.refreshCache(this.groups);
261    }  
262});