extjs4 pagingtoolbar refresh button 扩展

    <script type="text/javascript">
        Ext.onReady(function () {

            var simpsonsStore = Ext.create('Ext.data.Store',{
                storeId: 'simpsonsStore',fields: ['name','email','phone'],data: { 'items': [
                    { 'name': 'Lisa',"email": "lisa@simpsons.com","phone": "555-111-1224" },{ 'name': 'Bart',"email": "bart@simpsons.com","phone": "555-222-1234" },{ 'name': 'Homer',"email": "home@simpsons.com","phone": "555-222-1244" },{ 'name': 'Marge',"email": "marge@simpsons.com","phone": "555-222-1254" }
                 ]
                },proxy: {
                    type: 'memory',reader: {
                        type: 'json',root: 'items'
                    }
                }
            });

            var panel = Ext.create('Ext.grid.Panel',{
                title: 'Simpsons',//store: Ext.data.StoreManager.lookup('simpsonsStore'),store: simpsonsStore,bbar: { xtype: 'pagingtoolbar',displayInfo: true },//分页工具条
                columns: [
                            { header: 'Name',dataIndex: 'name' },{ header: 'Email',dataIndex: 'email',flex: 1 },{ header: 'Phone',dataIndex: 'phone' }
                ],height: 200,width: 400,renderTo: 'grids',buttons: [
                {
                    text: '重写刷新按钮',handler: function () {
                        var length = panel.dockedItems.keys.length;
                        var refreshStr = "";
                        for (var i = 0; i < length; i++) {
                            if (panel.dockedItems.keys[i].indexOf("pagingtoolbar") !== -1) {
                                refreshStr = panel.dockedItems.keys[i];
                            }
                        }
                        panel.dockedItems.get(refreshStr).child('#refresh').setHandler(
                             function () {
                                 alert('You clicked the button!');
                             }
                        );
                    }
                }]
            });
        });
    </script>

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