public function initialize()
{
$image = new Upload('fake_file');
$image->setModel(new FakeFileModel());
$image->setPreviewSize(array('width' => 100, 'height' => 100));
$image->getDecorator()->setTemplateName('jquery');
$image->setUploadUrl($this->url->get(['for' => 'testcrud', 'action' => 'upload']));
$image->setMode(Upload::MODE_MULTI);
$image->setMaxFiles(3);
$image->setExtensions(['jpg', 'png']);
$image->setMimeTypes(['image/jpeg', 'image/png']);
$image->setRenderPreview(true);
$image->setLabel('Image');
$image->getDecorator()->setDI($this->di);
$image->setAutoUpload(false);
$image->setButtonLabels(array('add' => 'Add image'));
$image->setTriggerType('button');
$image->setMaxFileSize('10MB');
$this->add($image);
$field = new Text('fake_field');
$field->addValidator(new PresenceOf());
$this->add($field);
}