source: Dev/trunk/src/client/dojox/app/widgets/_ScrollableMixin.js

// This module is modified from dojox/mobile/_ScrollableMixin and dojox/mobile/ScrollableView
define([
        "dojo/_base/declare",
        "dojo/_base/lang",
        "dojo/_base/array",
        "dojo/_base/window",
        "dojo/dom-class",
        "dijit/registry",
        "dojo/dom",
        "dojo/dom-construct",
        "dojox/mobile/scrollable"],
        function(declare, lang, array, win, domClass, registry, dom, domConstruct, Scrollable){
        // module:
        //              dojox/mobile/_ScrollableMixin
        // summary:
        //              Mixin for widgets to have a touch scrolling capability.

        return declare("dojox.app.widgets._ScrollableMixin", Scrollable, {
                // summary:
                //              Mixin for widgets to have a touch scrolling capability.
                // description:
                //              Actual implementation is in dojox/mobile/scrollable.js.
                //              scrollable.js is not a dojo class, but just a collection
                //              of functions. This module makes scrollable.js a dojo class.

                // scrollableParams: Object
                //              Parameters for dojox/mobile/scrollable.init().
                scrollableParams: null,

                // appBars: Boolean
                //              Enables the search for application-specific bars (header or footer).
                appBars: true, 

                // allowNestedScrolls: Boolean
                //              e.g. Allow ScrollableView in a SwapView.
                allowNestedScrolls: true,

                constructor: function(){
                        this.scrollableParams = {noResize: true}; // set noResize to true to match the way it was done in app/widgets/scrollable.js
                },

                destroy: function(){
                        this.cleanup();
                        this.inherited(arguments);
                },

                startup: function(){
                        if(this._started){ return; }
                        this.findAppBars();
                        var node, params = this.scrollableParams;
                        if(this.fixedHeader){
                                node = dom.byId(this.fixedHeader);
                                if(node.parentNode == this.domNode){ // local footer
                                        this.isLocalHeader = true;
                                }
                                params.fixedHeaderHeight = node.offsetHeight;
                        }
                        if(this.fixedFooter){
                                node = dom.byId(this.fixedFooter);
                                if(node.parentNode == this.domNode){ // local footer
                                        this.isLocalFooter = true;
                                        node.style.bottom = "0px";
                                }
                                params.fixedFooterHeight = node.offsetHeight;
                        }
                        
                        this.init(params);
                        this.inherited(arguments);
                        this.reparent();
                },

                // build scrollable container domNode. This method from dojox/mobile/ScrollableView
                buildRendering: function(){
                        this.inherited(arguments);
                        domClass.add(this.domNode, "mblScrollableView");
                        this.domNode.style.overflow = "hidden";
                        this.domNode.style.top = "0px";
                        this.containerNode = domConstruct.create("div", {className:"mblScrollableViewContainer"}, this.domNode);
                        this.containerNode.style.position = "absolute";
                        this.containerNode.style.top = "0px"; // view bar is relative
                        if(this.scrollDir === "v"){
                                this.containerNode.style.width = "100%";
                        }
                },

                // This method from dojox/mobile/ScrollableView
                reparent: function(){
                        // summary:
                        //              Moves all the children to containerNode.
                        var i, idx, len, c;
                        for(i = 0, idx = 0, len = this.domNode.childNodes.length; i < len; i++){
                                c = this.domNode.childNodes[idx];
                                // search for view-specific header or footer
                //              if(c === this.containerNode){
                                if(c === this.containerNode || this.checkFixedBar(c, true)){
                                        idx++;
                                        continue;
                                }
                                this.containerNode.appendChild(this.domNode.removeChild(c));
                        }
                },

                // This method from dojox/mobile/ScrollableView
                resize: function(){
                        // summary:
                        //              Calls resize() of each child widget.
                        this.inherited(arguments); // scrollable#resize() will be called
                        array.forEach(this.getChildren(), function(child){
                                if(child.resize){ child.resize(); }
                        });
                },


                findAppBars: function(){
                        // summary:
                        //              Search for application-specific header or footer.
                        if(!this.appBars){ return; }
                        var i, len, c;
                        for(i = 0, len = win.body().childNodes.length; i < len; i++){
                                c = win.body().childNodes[i];
                                this.checkFixedBar(c, false);
                        }
                        if(this.domNode.parentNode){
                                for(i = 0, len = this.domNode.parentNode.childNodes.length; i < len; i++){
                                        c = this.domNode.parentNode.childNodes[i];
                                        this.checkFixedBar(c, false);
                                }
                        }
                        this.fixedFooterHeight = this.fixedFooter ? this.fixedFooter.offsetHeight : 0;
                },

        
                checkFixedBar: function(/*DomNode*/node, /*Boolean*/local){
                        // summary:
                        //              Checks if the given node is a fixed bar or not.
                        if(node.nodeType === 1){
                                var fixed = node.getAttribute("data-app-constraint")
                                        || (registry.byNode(node) && registry.byNode(node)["data-app-constraint"]);
                        /*      if(fixed === "top"){
                                        domClass.add(node, "mblFixedHeaderBar");
                                        if(local){
                                                node.style.top = "0px";
                                                this.fixedHeader = node;
                                        }
                                        return fixed;
                                }else
                        */       
                                if(fixed === "bottom"){
                                        domClass.add(node, "mblFixedBottomBar");
                                        if(local){
                                                this.fixedFooter = node;
                                        }else{
                                                this._fixedAppFooter = node;
                                        }
                                        return fixed;
                                }
                        }
                        return null;
                }
                        
        });
});