form_upload.xml

<?xml version="1.0" encoding="UTF-8"?>

<panel-form xmlns="http://www.davinti.com.br/vitruvio/form/panel" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.davinti.com.br/vitruvio/form/panel https://bitbucket.org/davinTI/vitruvio-xds/raw/master/vitruvio-panel-form.xsd">
  <form formKey="formUpload" composer="VitruvioEditor:2.1.1-rc1.java8" width="50%" height="100%" target="DEFAULT">
    <name><![CDATA[Persistencai do form]]></name>
    <initScript language="JavaScript"><![CDATA[var vc = libService.loadScript('vaadinComponents');
function run() {
    
    var fileId = 28399;
    var file = vFileService.getFile(fileId);
    
    var resource = vc.fileResource(file);
    
    var widgetImagem = engine.getWidgetController('imagem');
    
    var image = widgetImagem.getComponent();
    image.setSource(resource);
}
]]></initScript>
    <components>
      <VerticalLayout width="100%" spacing="true" margin="true" visible="true" align="TOP_LEFT" height="100%" id="TFtSbeSz">
        <FileUploadWidget visible="true" align="TOP_LEFT" id="upload" action="NOTIFY_SCRIPT">
          <OnFileUploadScript language="JavaScript" provideVariables="false"><![CDATA[importClass(Packages.br.com.davinti.vitruvio.domain.sistema.Arquivo);

/* Carga da biblioteca JavaScript */
var vc = libService.loadScript('vaadinComponents');

// 
function onFileUpload(fileInfo) {
    var resource = vc.fileResource(fileInfo.getFile(), fileInfo.getFileName());
    
    var widgetImagem = engine.getWidgetController('imagem');
    
    var image = widgetImagem.getComponent();
    image.setSource(resource);
    
    
    // Persistindo imagem
    var meta = new Arquivo();
    meta.setNomeOriginal(fileInfo.getFileName());
    meta.setMime(fileInfo.getMime());
    
    var persistido = vFileService.persistFile(meta, fileInfo.getFile());
    engine.debug(persistido.getId());
    
    return true;
}]]></OnFileUploadScript>
        </FileUploadWidget>
        <ImageWidget visible="true" align="TOP_LEFT" id="imagem" expandRatio="1.0">
          <image>
            <base64/>
          </image>
        </ImageWidget>
      </VerticalLayout>
    </components>
  </form>
</panel-form>