I have a simple dropdown menu and I want the selected item to be something else than the first item. So how can I change the selection? I have already tried to add activeItem to it, but it doesn't seem to work.

Code:
xtype: 'select',
name: 'autoUpdateTime',
options: [{
    text: 'Never',
    value: 'Never'
}, {
    text: '1 minute',
    value: refreshTime1,
}, {
    text: '20 minutes',
    value: refreshTime2,
}, {
    text: '30 minutes',
    value: refreshTime3,
}]