source: Dev/trunk/src/client/dojox/widget/Loader.js

dojo.provide("dojox.widget.Loader");
dojo.deprecated("dojox.widget.Loader", "", "2.0");

dojo.require("dijit._Widget");
dojo.require("dijit._Templated");

dojo.declare("dojox.widget.Loader", [dijit._Widget,dijit._Templated], {
        // summary:
        //              a configurable global xhr-listener to display
        //              a loading message during running xhr's or to simply provide
        //              base-level topic to subscribe to for custom loading messages

        // loadIcon: String
        //              location to the icon used.
        loadIcon: dojo.moduleUrl("dojox.widget.Loader","icons/loading.gif"),

        // loadMessage: String
        //              string to use for progress loading
        loadMessage: 'Loading ...',

        // hasVisuals: Boolean
        //              true to display a fixed loading message in TR cornder, false to unly provide
        //              "Loader" topic to subscribe to for your own custom loading message.
        hasVisuals: true,

        // attachToPointer
        //              true to use visual indicator where cursor is
        attachToPointer: true,

        // duration: Integer
        //              time in ms to toggle in/out the visual load indicator
        duration: 125,

        // _offset: Integer
        //              distance in px from the mouse pointer to show attachToPointer avatar
        _offset: 16,

        // holder for mousemove connection
        _pointerConnect: null,
        _xhrStart: null,
        _xhrEnd: null,

        templateString: '<div dojoAttachPoint="loadNode" class="dojoxLoader">'
                +'<img src="${loadIcon}" class="dojoxLoaderIcon"> <span dojoAttachPoint="loadMessageNode" class="dojoxLoaderMessage"></span>'
                +'</div>',
        
        postCreate: function(){
                // summary:
                //              setup the loader

                if(!this.hasVisuals){
                        this.loadNode.style.display = "none"; // _destroy()?
                }else{
                        if(this.attachToPointer){
                                dojo.removeClass(this.loadNode,"dojoxLoader");
                                dojo.addClass(this.loadNode,"dojoxLoaderPointer");
                        }
                        this._hide();
                }
                this._setMessage(this.loadMessage);

                // FIXME: create our connections.  would be easier, and this might be redundant
                // if Deferred published something. XHR published stuff. FIXME to use that.
                this._xhrStart = this.connect(dojo,"_ioSetArgs","_show");
                this._xhrEnd = this.connect(dojo.Deferred.prototype,"_fire","_hide");

        },

        _setMessage: function(/* String */ message){
                // summary:
                //              set's the message in the loader
                this.loadMessageNode.innerHTML = message;
        },

        _putLoader: function(/* Event */ e){
                // summary:
                //              place the floating loading element based on mousemove connection position
                dijit.placeOnScreen(this.loadNode,{ x: e.clientX+this._offset, y:e.clientY+this._offset }, ["TL","BR"]);
        },

        _show: function(){
                // summary:
                //              publish and show progress indicator
                dojo.publish("Loader",[{ message: 'started' }]);
                if(this.hasVisuals){
                        if(this.attachToPointer){
                                this._pointerConnect = this.connect(document,"onmousemove","_putLoader");
                        }
                        dojo.style(this.loadNode, {
                                opacity:0, display:""
                        });
                        dojo.fadeIn({ node: this.loadNode, duration:this.duration }).play();
                }
        },

        _hide: function(){
                // summary:
                //              publish "xhr ended" and hide progress indicator
                dojo.publish("Loader",[{ message: 'ended' }]);
                if(this.hasVisuals){
                        if(this.attachToPointer){
                                this.disconnect(this._pointerConnect);
                        }
                        dojo.fadeOut({
                                node: this.loadNode,
                                duration:this.duration,
                                onEnd: dojo.partial(dojo.style, this.loadNode, "display", "none")
                        }).play();
                }
        }

});