let layout = new w2layout({

    name    : 'layout',

    panels  : [

        { type: 'top', size: 40 },

        { type: 'main', content: 'This is main panel',

            tabs: {

                active: 'tab2',

                tabs: [

                    { id: 'tab1', text: 'Tab 1' },

                    { id: 'tab2', text: 'Tab 2' },

                    { id: 'tab3', text: 'Tab 3' }

                ],

                onClick(event) {

                    console.log('event');

                }

            }

        },

        { type: 'preview', size: 200 }

    ]

});

​

w2ui.layout.toggleTabs('main');

​