broken.js

Ext.require(['Ext.grid.*', 'Ext.data.*', 'Ext.util.*', 'Ext.state.*', 'Ext.window.*']);

Ext.onReady(function() {
  var myData = [
    ['3m Co']];

  var store = Ext.create('Ext.data.ArrayStore', {
    fields: [
      {
        name: 'company'
      },
    ],
    data: myData
  });

  var columns = [
    {
      text: 'Company',
      flex: 1,
      sortable: false,
      dataIndex: 'company'
    }
  ];

  var grid = Ext.create('Ext.grid.Panel', {
    store: new Ext.data.ArrayStore(),
    stateful: true,
    stateId: 'stateGrid',
    height: 350,
    columns: [],
    width: 600,
    title: 'Array Grid',
    viewConfig: {
      stripeRows: true
    }
  });

  new Ext.Window({
    items: [
      {
        xtype: 'panel',
        border: false,
        layout: {
          type: 'card'
        },
        items: [
          grid
        ]
      }
    ],
    renderTo: Ext.getBody()
  }).show();

  setTimeout(function() {
    grid.reconfigure(store, columns);
  }, 1000);
});

working.js

Ext.require(['Ext.grid.*', 'Ext.data.*', 'Ext.util.*', 'Ext.state.*', 'Ext.window.*']);

Ext.onReady(function() {
  var myData = [
    ['3m Co'],
    ['Alcoa Inc'],
    ['Altria Group Inc'],
    ['American Express Company'],
    ['American International Group, Inc.'],
    ['AT&T Inc.'],
    ['Boeing Co.'],
    ['Caterpillar Inc.'],
    ['Citigroup, Inc.'],
    ['E.I. du Pont de Nemours and Company'],
    ['Exxon Mobil Corp'],
    ['General Electric Company'],
    ['General Motors Corporation'],
    ['Hewlett-Packard Co.'],
    ['Honeywell Intl Inc'],
    ['Intel Corporation'],
    ['International Business Machines'],
    ['Johnson & Johnson'],
    ['JP Morgan & Chase & Co'],
    ['McDonald\'s Corporation'],
    ['Merck & Co., Inc.'],
    ['Microsoft Corporation'],
    ['Pfizer Inc'],
    ['The Coca-Cola Company'],
    ['The Home Depot, Inc.'],
    ['The Procter & Gamble Company'],
    ['United Technologies Corporation'],
    ['Verizon Communications'],
    ['Wal-Mart Stores, Inc.']
  ];

  var store = Ext.create('Ext.data.ArrayStore', {
    fields: [
      {
        name: 'company'
      },
    ],
    data: myData
  });

  var columns = [
    {
      text: 'Company',
      flex: 1,
      sortable: false,
      dataIndex: 'company'
    }
  ];

  var grid = Ext.create('Ext.grid.Panel', {
    store: new Ext.data.ArrayStore(),
    stateful: true,
    stateId: 'stateGrid',
    height: 350,
    columns: [],
    width: 600,
    title: 'Array Grid',
    viewConfig: {
      stripeRows: true
    }
  });

  new Ext.Window({
    items: [
      {
        xtype: 'panel',
        border: false,
        layout: {
          type: 'card'
        },
        items: [
          grid
        ]
      }
    ],
    renderTo: Ext.getBody()
  }).show();

  setTimeout(function() {
    grid.reconfigure(store, columns);
  }, 1000);
});