(function() {
    var uploader = new MultipleUpload('#demo', {
        uploadUrl: '/api/upload',
        multiple: true
    });
    document.getElementById('toggle-btn').addEventListener('click', function() {
        if (uploader.isEnabled()) {
            uploader.disable();
            document.getElementById('state-label').textContent = 'Disabled';
        } else {
            uploader.enable();
            document.getElementById('state-label').textContent = 'Enabled';
        }
    });
})();