source: Dev/trunk/src/client/dojox/charting/StoreSeries.js

define(["dojo/_base/array", "dojo/_base/declare", "dojo/_base/Deferred"], 
  function(arr, declare, Deferred){
        
        return declare("dojox.charting.StoreSeries", null, {
                constructor: function(store, kwArgs, value){
                        // summary:
                        //              Series adapter for dojo object stores (dojo.store).
                        // store: Object
                        //              A dojo object store.
                        // kwArgs: Object
                        //              A store-specific keyword parameters used for querying objects.
                        //              See dojo.store docs
                        // value: Function|Object|String
                        //              Function, which takes an object handle, and
                        //              produces an output possibly inspecting the store's item. Or
                        //              a dictionary object, which tells what names to extract from
                        //              an object and how to map them to an output. Or a string, which
                        //              is a numeric field name to use for plotting. If undefined, null
                        //              or empty string (the default), "value" field is extracted.
                        this.store = store;
                        this.kwArgs = kwArgs;
        
                        if(value){
                                if(typeof value == "function"){
                                        this.value = value;
                                }else if(typeof value == "object"){
                                        this.value = function(object){
                                                var o = {};
                                                for(var key in value){
                                                        o[key] = object[value[key]];
                                                }
                                                return o;
                                        };
                                }else{
                                        this.value = function(object){
                                                return object[value];
                                        };
                                }
                        }else{
                                this.value = function(object){
                                        return object.value;
                                };
                        }
        
                        this.data = [];

                        this._initialRendering = false;
                        this.fetch();
                },
        
                destroy: function(){
                        // summary:
                        //              Clean up before GC.
                        if(this.observeHandle){
                                this.observeHandle.remove();
                        }
                },
        
                setSeriesObject: function(series){
                        // summary:
                        //              Sets a dojox.charting.Series object we will be working with.
                        // series: dojox/charting/Series
                        //              Our interface to the chart.
                        this.series = series;
                },
        
                // store fetch loop
        
                fetch: function(){
                        // summary:
                        //              Fetches data from the store and updates a chart.
                        var self = this;
                        if(this.observeHandle){
                                this.observeHandle.remove();
                        }
                        var results = this.store.query(this.kwArgs.query, this.kwArgs);
                        Deferred.when(results, function(objects){
                                self.objects = objects;
                                update();
                        });
                        if(results.observe){
                                this.observeHandle = results.observe(update, true);
                        }
                        function update(){
                                self.data = arr.map(self.objects, function(object){
                                        return self.value(object, self.store);
                                });
                                self._pushDataChanges();
                        }
                },
        
                _pushDataChanges: function(){
                        if(this.series){
                                this.series.chart.updateSeries(this.series.name, this, this._initialRendering);
                                this._initialRendering = false;
                                this.series.chart.delayedRender();
                        }
                }
        
        });
});