store.js

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/*
 * Ext JS Library 1.1 RC 1
 * Copyright(c) 2006-2007, Ext JS, LLC.
 * [e-mail]
 * 
 * http://www.extjs.com/license
 */

/**
 * @class Ext.data.Store
 * @extends Ext.util.Observable
 * The Store class encapsulates a client side cache of {@link Ext.data.Record} objects which provide input data
 * for widgets such as the Ext.grid.Grid, or the Ext.form.ComboBox.<br>
 * <p>
 * A Store object uses an implementation of {@link Ext.data.DataProxy} to access a data object unless you call loadData() directly and pass in your data. The Store object
 * has no knowledge of the format of the data returned by the Proxy.<br>
 * <p>
 * A Store object uses its configured implementation of {@link Ext.data.DataReader} to create {@link Ext.data.Record}
 * instances from the data object. These records are cached and made available through accessor functions.
 * @constructor
 * Creates a new Store.
 * @param {Object} config A config object containing the objects needed for the Store to access data,
 * and read the data into Records.
 */
Ext.data.Store = function(config){
    this.data = new Ext.util.MixedCollection(false);
    this.data.getKey = function(o){
        return o.id;
    };
    this.baseParams = {};
    // private
    this.paramNames = {
        "start" : "start",
        "limit" : "limit",
        "sort" : "sort",
        "dir" : "dir"
    };

    if(config && config.data){
        this.inlineData = config.data;
        delete config.data;
    }

    Ext.apply(this, config);

    if(this.reader){ // reader passed
        if(!this.recordType){
            this.recordType = this.reader.recordType;
        }
        if(this.reader.onMetaChange){
            this.reader.onMetaChange = this.onMetaChange.createDelegate(this);
        }
    }

    if(this.recordType){
        this.fields = this.recordType.prototype.fields;
    }
    this.modified = [];

    this.addEvents({
        /**
         * @event datachanged
         * Fires when the data cache has changed, and a widget which is using this Store
         * as a Record cache should refresh its view.
         * @param {Store} this
         */
        datachanged : true,
        /**
         * @event metachange
         * Fires when this stores reader provides new meta data (fields). This is currently only support for JsonReaders.
         * @param {Store} this
         * @param {Object} meta The JSON meta data
         */
        metachange : true,
        /**
         * @event add
         * Fires when Records have been added to the Store
         * @param {Store} this
         * @param {Ext.data.Record[]} records The array of Records added
         * @param {Number} index The index at which the record(s) were added
         */
        add : true,
        /**
         * @event remove
         * Fires when Records have been removed from the Store
         * @param {Store} this
         * @param {Ext.data.Record} record The Record that was removed
         * @param {Number} index The index at which the record was removed
         */
        remove : true,
        /**
         * @event update
         * Fires when Records have been updated
         * @param {Store} this
         * @param {Ext.data.Record} record The Record that was updated
         * @param {String} operation The update operation being performed.  Value may be one of:
         * <pre><code>
 Ext.data.Record.EDIT
 Ext.data.Record.REJECT
 Ext.data.Record.COMMIT
         * </code></pre>
         */
        update : true,
        /**
         * @event clear
         * Fires when the data cache has been cleared.
         * @param {Store} this
         */
        clear : true,
        /**
         * @event beforeload
         * Fires before a request is made for a new data object.  If the beforeload handler returns false
         * the load action will be canceled.
         * @param {Store} this
         * @param {Object} options The loading options that were specified (see {@link #load} for details)
         */
        beforeload : true,
        /**
         * @event load
         * Fires after a new set of Records has been loaded.
         * @param {Store} this
         * @param {Ext.data.Record[]} records The Records that were loaded
         * @param {Object} options The loading options that were specified (see {@link #load} for details)
         */
        load : true,
        /**
         * @event loadexception
         * Fires if an exception occurs in the Proxy during loading.
         * Called with the signature of the Proxy's "loadexception" event.
         */
        loadexception : true
    });

    if(this.proxy){
        this.relayEvents(this.proxy,  ["loadexception"]);
    }
    this.sortToggle = {};

    Ext.data.Store.superclass.constructor.call(this);

    if(this.inlineData){
        this.loadData(this.inlineData);
        delete this.inlineData;
    }
};
Ext.extend(Ext.data.Store, Ext.util.Observable, {
    /**
    * @cfg {Ext.data.DataProxy} proxy The Proxy object which provides access to a data object.
    */
    /**
    * @cfg {Array} data Inline data to be loaded when the store is initialized.
    */
    /**
    * @cfg {Ext.data.Reader} reader The Reader object which processes the data object and returns
    * an Array of Ext.data.record objects which are cached keyed by their <em>id</em> property.
    */
    /**
    * @cfg {Object} baseParams An object containing properties which are to be sent as parameters
    * on any HTTP request
    */
    /**
    * @cfg {Object} sortInfo A config object in the format: {field: "fieldName", direction: "ASC|DESC"}
    */
    /**
    * @cfg {boolean} remoteSort True if sorting is to be handled by requesting the Proxy to provide a refreshed
    * version of the data object in sorted order, as opposed to sorting the Record cache in place (defaults to false).
    */
    remoteSort : false,

    // private
    lastOptions : null,

    /**
     * Add Records to the Store and fires the add event.
     * @param {Ext.data.Record[]} records An Array of Ext.data.Record objects to add to the cache.
     */
    add : function(records){
        records = [].concat(records);
        for(var i = 0, len = records.length; i < len; i++){
            records[i].join(this);
        }
        var index = this.data.length;
        this.data.addAll(records);
        this.fireEvent("add", this, records, index);
    },

    /**
     * Remove a Record from the Store and fires the remove event.
     * @param {Ext.data.Record} record Th Ext.data.Record object to remove from the cache.
     */
    remove : function(record){
        var index = this.data.indexOf(record);
        this.data.removeAt(index);
        this.fireEvent("remove", this, record, index);
    },

    /**
     * Remove all Records from the Store and fires the clear event.
     */
    removeAll : function(){
        this.data.clear();
        this.fireEvent("clear", this);
    },

    /**
     * Inserts Records to the Store at the given index and fires the add event.
     * @param {Number} index The start index at which to insert the passed Records.
     * @param {Ext.data.Record[]} records An Array of Ext.data.Record objects to add to the cache.
     */
    insert : function(index, records){
        records = [].concat(records);
        for(var i = 0, len = records.length; i < len; i++){
            this.data.insert(index, records[i]);
            records[i].join(this);
        }
        this.fireEvent("add", this, records, index);
    },

    /**
     * Get the index within the cache of the passed Record.
     * @param {Ext.data.Record} record The Ext.data.Record object to to find.
     * @return {Number} The index of the passed Record. Returns -1 if not found.
     */
    indexOf : function(record){
        return this.data.indexOf(record);
    },

    /**
     * Get the index within the cache of the Record with the passed id.
     * @param {String} id The id of the Record to find.
     * @return {Number} The index of the Record. Returns -1 if not found.
     */
    indexOfId : function(id){
        return this.data.indexOfKey(id);
    },

    /**
     * Get the Record with the specified id.
     * @param {String} id The id of the Record to find.
     * @return {Ext.data.Record} The Record with the passed id. Returns undefined if not found.
     */
    getById : function(id){
        return this.data.key(id);
    },

    /**
     * Get the Record at the specified index.
     * @param {Number} index The index of the Record to find.
     * @return {Ext.data.Record} The Record at the passed index. Returns undefined if not found.
     */
    getAt : function(index){
        return this.data.itemAt(index);
    },

    /**
     * Returns a range of Records between specified indices.
     * @param {Number} startIndex (optional) The starting index (defaults to 0)
     * @param {Number} endIndex (optional) The ending index (defaults to the last Record in the Store)
     * @return {Ext.data.Record[]} An array of Records
     */
    getRange : function(start, end){
        return this.data.getRange(start, end);
    },

    // private
    storeOptions : function(o){
        o = Ext.apply({}, o);
        delete o.callback;
        delete o.scope;
        this.lastOptions = o;
    },

    /**
     * Loads the Record cache from the configured Proxy using the configured Reader.
     * <p>
     * If using remote paging, then the first load call must specify the <em>start</em>
     * and <em>limit</em> properties in the options.params property to establish the initial
     * position within the dataset, and the number of Records to cache on each read from the Proxy.
     * <p>
     * <strong>It is important to note that for remote data sources, loading is asynchronous,
     * and this call will return before the new data has been loaded. Perform any post-processing
     * in a callback function, or in a "load" event handler.</strong>
     * <p>
     * @param {Object} options An object containing properties which control loading options:<ul>
     * <li>params {Object} An object containing properties to pass as HTTP parameters to a remote data source.</li>
     * <li>callback {Function} A function to be called after the Records have been loaded. The callback is
     * passed the following arguments:<ul>
     * <li>r : Ext.data.Record[]</li>
     * <li>options: Options object from the load call</li>
     * <li>success: Boolean success indicator</li></ul></li>
     * <li>scope {Object} Scope with which to call the callback (defaults to the Store object)</li>
     * <li>add {Boolean} indicator to append loaded records rather than replace the current cache.</li>
     * </ul>
     */
    load : function(options){
        options = options || {};
        if(this.fireEvent("beforeload", this, options) !== false){
            this.storeOptions(options);
            var p = Ext.apply(options.params || {}, this.baseParams);
            if(this.sortInfo && this.remoteSort){
                var pn = this.paramNames;
                p[pn["sort"]] = this.sortInfo.field;
                p[pn["dir"]] = this.sortInfo.direction;
            }
            this.proxy.load(p, this.reader, this.loadRecords, this, options);
        }
    },

    /**
     * Reloads the Record cache from the configured Proxy using the configured Reader and
     * the options from the last load operation performed.
     * @param {Object} options (optional) An object containing properties which may override the options
     * used in the last load operation. See {@link #load} for details (defaults to null, in which case
     * the most recently used options are reused).
     */
    reload : function(options){
        this.load(Ext.applyIf(options||{}, this.lastOptions));
    },