Page reloads every time I expand a panel

[Mandeep]

Hi,

We are using ExtJS 4.1 version. We have a ViewPort with two panels one in the center and other on the west. Our issue is that every time west pane is collapsed and then expanded then the page/url reloads. Is there anyway to stop it from reloading every time it is expanded. Any help will be greatly appreciated.

    var view = new Ext.Viewport(
    {
        xtype:'panel',
        id: 'grid-viewport',
        stateId: viewStateId,
        layout: 'border',
        stateful: true,


        items: [
            {
                xtype:'panel',
                autoDestroy: true,
                region: 'center',
                width:  '80%',
                bodyBorder: false,
                layout: 'fit',
                stateId: viewStateId + '-Center',
                stateful: true,
                loader: {
                    url: "/Folder1/Grid.jsp,
                    contentType: 'html',
                    autoLoad: true,
                    loadMask: true
                }
         },
            {   /* This one reloads every time on expand*/
                region: 'west',
                id: 'filterPane',
                autoDestroy: true,
                collapsible: true,
                title: title_Filter,
                split: true,
                bodyBorder: false,
                stateId: viewStateId + '-West',
                stateful: true,
                width: 320,
                loader: {
                    url: "/Folder2/NavTree.jsp,
                    contentType: 'html',
                    autoLoad: true,
                    loadMask: true
                }
            }


       ]
    });

[Mandeep]

Please help