I am trying out Ext 4 and i ran into something it think is a bug.
I have hooked up a JsonStore into a grid. I added the PagingToolbar to the DockedItems.

When the store is initialized and the data is loaded, the images on the PagingToolbar remain greyed out.
The image click handlers operate properly, but the inactive state remains on the elements.

PagingToolbar.jpg

Code:
      
var resourceJsonProxy = new Ext.data.HttpProxy({
            url: '/Resource/GetResources',
            model: 'ResourceItem',
            reader: {
                type: 'json',
                root: 'Data',
                totalProperty: 'RecordCount',
                messageProperty: 'ErrorMessage',
                successProperty: 'Success'
            },
            actionMethods: {
                create: 'POST',
                read: 'POST',
                update: 'POST',
                destroy: 'POST'
            }            
        });

        var resourceStore = new Ext.data.JsonStore({
            remoteSort: true,
            remoteFilter: true,
            sortOnLoad: true,
            
            startParam: 'Start',
            limitParam: 'Limit',
            sortParam: 'Sort',
            filterParam: 'Filter',
            sortInfo: {
                property: 'ResourcePath',
                direction: 'ASC'
            },
            model: 'ResourceItem',
            proxy: resourceJsonProxy,
            listeners: {
                load: this.onLoad,
                scope: this
            }
        });

        var pageSize = 25;

        Ext.apply(this, {
            cls: 'resource-grid',
            store: resourceStore,
            dockedItems: [
                new Ext.PagingToolbar({
                    store: resourceStore,
                    displayInfo: true,
                    displayMsg: 'Displaying resources {0} - {1} of {2}',
                    emptyMsg: "No resources to display",
                    pageSize: pageSize,
                    prependButtons: true
                })            
            ],
            items: [{
                itemId: 'resource-grid',
                plugins: [{
                    pluginId: 'preview',
                    ptype: 'preview',
                    bodyField: 'ResourceValue',
                    previewExpanded: false
                }],
                headers: [{
                    text: 'Resource',
                    dataIndex: 'ResourcePath',
                    flex: 1,
                    renderer: this.formatTitle
                }, {
                    text: 'Culture',
                    dataIndex: 'CultureCode',
                    hidden: true,
                    width: 200

                }],
                viewConfig: {
                    listeners: {
                        scope: this,
                        dblclick: this.onRowDblClick
                    }
                }
            }]
        });