let layout = new w2layout({

    name    : 'layout',

    panels  : [

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

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

            toolbar: {

                items: [

                    { id: 'bt1', type: 'button', text: 'Button 1', img: 'icon-page' },

                    { id: 'bt2', type: 'button', text: 'Button 2', img: 'icon-page' },

                    { id: 'bt3', type: 'button', text: 'Button 3', img: 'icon-page' }

                ],

                onClick(event) {

                    console.log('event');

                }

            }

        },

        { type: 'preview', size: 200 }

    ]

});

​

w2ui.layout.toggleToolbar('main');

​