Insert dynamic listbox options in Tinymce popup editor

So the problem with the values helper was that it will only take array of objects and i was passing a string…I have corrected the code by passing an array of objects..Below is the corrected code..

body: [
        {
            type: 'listbox',
            name: 'type',
            label: 'Panel Type',
            value: type,
            'values': get_author_list(),
            tooltip: 'Select the type of panel you want'
        },
]
.....

function get_authors_list() {
    var result = [];
    var d = {};
    d['text'] = 'Default';
    d['value'] = 'default';
    result.push(d);
    return result;
}