gistfile1.js

    Ext.create('Ext.form.Panel', {
        title: 'Checkbox Group',
        width: 300,
        height: 125,
        bodyPadding: 10,
        renderTo: Ext.get('cbg'),
        items: [{
            xtype: 'checkboxgroup',
            fieldLabel: 'Two Columns',
            // Arrange checkboxes into two columns, distributed vertically
            columns: 2,
            vertical: true,
            items: [{
                boxLabel: 'Item 1',
                name: 'rb',
                inputValue: '1'
            }, {
                boxLabel: 'Item 2',
                name: 'rb',
                inputValue: '2',
                checked: true
            }, {
                boxLabel: 'Item 3',
                name: 'rb',
                inputValue: '3'
            }, {
                boxLabel: 'Item 4',
                name: 'rb',
                inputValue: '4'
            }, {
                boxLabel: 'Item 5',
                name: 'rb',
                inputValue: '5'
            }, {
                boxLabel: 'Item 6',
                name: 'rb',
                inputValue: '6'
            }]
        }]
    });