updatemanager.js

ajax框架extjs是一套完整的富客户端解决方案

/*
 * Ext JS Library 2.2
 * Copyright(c) 2006-2008, Ext JS, LLC.
 * [e-mail]
 * 
 * http://extjs.com/license
 */

/**
 * @class Ext.Updater
 * @extends Ext.util.Observable
 * Provides AJAX-style update capabilities for Element objects.  Updater can be used to {@link #update} an Element once,
 * or you can use {@link #startAutoRefresh} to set up an auto-updating Element on a specific interval.<br><br>
 * Usage:<br>
 * <pre><code>
 * // Get it from a Ext.Element object
 * var el = Ext.get("foo");
 * var mgr = el.getUpdater();
 * mgr.update({
        url: "http://myserver.com/index.php",
        params: {
            param1: "foo",
            param2: "bar"
        }
 * });
 * ...
 * mgr.formUpdate("myFormId", "http://myserver.com/index.php");
 * <br>
 * // or directly (returns the same Updater instance)
 * var mgr = new Ext.Updater("myElementId");
 * mgr.startAutoRefresh(60, "http://myserver.com/index.php");
 * mgr.on("update", myFcnNeedsToKnow);
 * <br>
 * // short handed call directly from the element object
 * Ext.get("foo").load({
        url: "bar.php",
        scripts: true,
        params: "param1=foo&amp;param2=bar",
        text: "Loading Foo..."
 * });
 * </code></pre>
 * @constructor
 * Create new Updater directly.
 * @param {Mixed} el The element to update
 * @param {Boolean} forceNew (optional) By default the constructor checks to see if the passed element already
 * has an Updater and if it does it returns the same instance. This will skip that check (useful for extending this class).
 */
Ext.Updater = Ext.extend(Ext.util.Observable, {
    constructor: function(el, forceNew){
        el = Ext.get(el);
        if(!forceNew && el.updateManager){
            return el.updateManager;
        }
        /**
         * The Element object
         * @type Ext.Element
         */
        this.el = el;
        /**
         * Cached url to use for refreshes. Overwritten every time update() is called unless "discardUrl" param is set to true.
         * @type String
         */
        this.defaultUrl = null;

        this.addEvents(
            /**
             * @event beforeupdate
             * Fired before an update is made, return false from your handler and the update is cancelled.
             * @param {Ext.Element} el
             * @param {String/Object/Function} url
             * @param {String/Object} params
             */
            "beforeupdate",
            /**
             * @event update
             * Fired after successful update is made.
             * @param {Ext.Element} el
             * @param {Object} oResponseObject The response Object
             */
            "update",
            /**
             * @event failure
             * Fired on update failure.
             * @param {Ext.Element} el
             * @param {Object} oResponseObject The response Object
             */
            "failure"
        );
        var d = Ext.Updater.defaults;
        /**
         * Blank page URL to use with SSL file uploads (defaults to {@link Ext.Updater.defaults#sslBlankUrl}).
         * @type String
         */
        this.sslBlankUrl = d.sslBlankUrl;
        /**
         * Whether to append unique parameter on get request to disable caching (defaults to {@link Ext.Updater.defaults#disableCaching}).
         * @type Boolean
         */
        this.disableCaching = d.disableCaching;
        /**
         * Text for loading indicator (defaults to {@link Ext.Updater.defaults#indicatorText}).
         * @type String
         */
        this.indicatorText = d.indicatorText;
        /**
         * Whether to show indicatorText when loading (defaults to {@link Ext.Updater.defaults#showLoadIndicator}).
         * @type String
         */
        this.showLoadIndicator = d.showLoadIndicator;
        /**
         * Timeout for requests or form posts in seconds (defaults to {@link Ext.Updater.defaults#timeout}).
         * @type Number
         */
        this.timeout = d.timeout;
        /**
         * True to process scripts in the output (defaults to {@link Ext.Updater.defaults#loadScripts}).
         * @type Boolean
         */
        this.loadScripts = d.loadScripts;
        /**
         * Transaction object of the current executing transaction, or null if there is no active transaction.
         */
        this.transaction = null;
        /**
         * Delegate for refresh() prebound to "this", use myUpdater.refreshDelegate.createCallback(arg1, arg2) to bind arguments
         * @type Function
         */
        this.refreshDelegate = this.refresh.createDelegate(this);
        /**
         * Delegate for update() prebound to "this", use myUpdater.updateDelegate.createCallback(arg1, arg2) to bind arguments
         * @type Function
         */
        this.updateDelegate = this.update.createDelegate(this);
        /**
         * Delegate for formUpdate() prebound to "this", use myUpdater.formUpdateDelegate.createCallback(arg1, arg2) to bind arguments
         * @type Function
         */
        this.formUpdateDelegate = this.formUpdate.createDelegate(this);

        if(!this.renderer){
         /**
          * The renderer for this Updater (defaults to {@link Ext.Updater.BasicRenderer}).
          */
        this.renderer = this.getDefaultRenderer();
        }
        Ext.Updater.superclass.constructor.call(this);
    },
    /**
     * This is an overrideable method which returns a reference to a default
     * renderer class if none is specified when creating the Ext.Updater.
     * Defaults to {@link Ext.Updater.BasicRenderer}
     */
    getDefaultRenderer: function() {
        return new Ext.Updater.BasicRenderer();
    },
    /**
     * Get the Element this Updater is bound to
     * @return {Ext.Element} The element
     */
    getEl : function(){
        return this.el;
    },

    /**
     * Performs an <b>asynchronous</b> request, updating this element with the response.
     * If params are specified it uses POST, otherwise it uses GET.<br><br>
     * <b>Note:</b> Due to the asynchronous nature of remote server requests, the Element
     * will not have been fully updated when the function returns. To post-process the returned
     * data, use the callback option, or an <b><tt>update</tt></b> event handler.
     * @param {Object} options A config object containing any of the following options:<ul>
     * <li>url : <b>String/Function</b><p class="sub-desc">The URL to request or a function which
     * <i>returns</i> the URL (defaults to the value of {@link Ext.Ajax#url} if not specified).</p></li>
     * <li>method : <b>String</b><p class="sub-desc">The HTTP method to
     * use. Defaults to POST if the <tt>params</tt> argument is present, otherwise GET.</p></li>
     * <li>params : <b>String/Object/Function</b><p class="sub-desc">The
     * parameters to pass to the server (defaults to none). These may be specified as a url-encoded
     * string, or as an object containing properties which represent parameters,
     * or as a function, which returns such an object.</p></li>
     * <li>scripts : <b>Boolean</b><p class="sub-desc">If <tt>true</tt>
     * any &lt;script&gt; tags embedded in the response text will be extracted
     * and executed (defaults to {@link Ext.Updater.defaults#loadScripts}). If this option is specified,
     * the callback will be called <i>after</i> the execution of the scripts.</p></li>
     * <li>callback : <b>Function</b><p class="sub-desc">A function to
     * be called when the response from the server arrives. The following
     * parameters are passed:<ul>
     * <li><b>el</b> : Ext.Element<p class="sub-desc">The Element being updated.</p></li>
     * <li><b>success</b> : Boolean<p class="sub-desc">True for success, false for failure.</p></li>
     * <li><b>response</b> : XMLHttpRequest<p class="sub-desc">The XMLHttpRequest which processed the update.</p></li>
     * <li><b>options</b> : Object<p class="sub-desc">The config object passed to the update call.</p></li></ul>
     * </p></li>
     * <li>scope : <b>Object</b><p class="sub-desc">The scope in which
     * to execute the callback (The callback's <tt>this</tt> reference.) If the
     * <tt>params</tt> argument is a function, this scope is used for that function also.</p></li>
     * <li>discardUrl : <b>Boolean</b><p class="sub-desc">By default, the URL of this request becomes
     * the default URL for this Updater object, and will be subsequently used in {@link #refresh}
     * calls.  To bypass this behavior, pass <tt>discardUrl:true</tt> (defaults to false).</p></li>
     * <li>timeout : <b>Number</b><p class="sub-desc">The number of seconds to wait for a response before
     * timing out (defaults to {@link Ext.Updater.defaults#timeout}).</p></li>
     * <li>text : <b>String</b><p class="sub-desc">The text to use as the innerHTML of the
     * {@link Ext.Updater.defaults#indicatorText} div (defaults to 'Loading...').  To replace the entire div, not
     * just the text, override {@link Ext.Updater.defaults#indicatorText} directly.</p></li>
     * <li>nocache : <b>Boolean</b><p class="sub-desc">Only needed for GET
     * requests, this option causes an extra, auto-generated parameter to be appended to the request
     * to defeat caching (defaults to {@link Ext.Updater.defaults#disableCaching}).</p></li></ul>
     * <p>
     * For example:
<pre><code>
um.update({
    url: "your-url.php",
    params: {param1: "foo", param2: "bar"}, // or a URL encoded string
    callback: yourFunction,
    scope: yourObject, //(optional scope)
    discardUrl: true,
    nocache: true,
    text: "Loading...",
    timeout: 60,
    scripts: false // Save time by avoiding RegExp execution.
});
</code></pre>
     */
    update : function(url, params, callback, discardUrl){
        if(this.fireEvent("beforeupdate", this.el, url, params) !== false){
            var cfg, callerScope;
            if(typeof url == "object"){ // must be config object
                cfg = url;
                url = cfg.url;
                params = params || cfg.params;
                callback = callback || cfg.callback;
                discardUrl = discardUrl || cfg.discardUrl;
                callerScope = cfg.scope;
                if(typeof cfg.nocache != "undefined"){this.disableCaching = cfg.nocache;};
                if(typeof cfg.text != "undefined"){this.indicatorText = '<div class="loading-indicator">'+cfg.text+"</div>";};
                if(typeof cfg.scripts != "undefined"){this.loadScripts = cfg.scripts;};
                if(typeof cfg.timeout != "undefined"){this.timeout = cfg.timeout;};
            }
            this.showLoading();

            if(!discardUrl){
                this.defaultUrl = url;
            }
            if(typeof url == "function"){
                url = url.call(this);
            }

            var o = Ext.apply({}, {
                url : url,
                params: (typeof params == "function" && callerScope) ? params.createDelegate(callerScope) : params,
                success: this.processSuccess,
                failure: this.processFailure,
                scope: this,
                callback: undefined,
                timeout: (this.timeout*1000),
                disableCaching: this.disableCaching,
                argument: {
                    "options": cfg,
                    "url": url,
                    "form": null,
                    "callback": callback,
                    "scope": callerScope || window,
                    "params": params
                }