sets toolbar mode and configuration
webix.ui({
    view:"spreadsheet",
    data: base_data,
    toolbar: "full"
});
To hide the toolbar, set the property to false. To show all available buttons on the toolbar, set the property to "full".
To make a multi-row toolbar, use the "toolbar" collection. Read more about it here.
toolbar: [
    {
        rows:[
          {
            margin: 2,
            cols: [
                {$button: "undo"},
                {$button: "redo"}
            ]
          },
          {},
          {template: "Undo/Redo", view: "ssheet-bar-title", height: 24}
        ]
    },
    {view: "ssheet-separator"},
    {
        rows:[
           {
             margin: 2,
             cols:[
                {$button: "font-family", width: 167},
                {$button: "font-size", width: 90}
             ]
           },
           ...
        ]
    },
    ...
]