if(propz.containsKey("text")) {
HFlexBox text_row = new HFlexBox();
text_row.setBoxAlign(FlexBox.Align.Stretch);
text_row.add(new Label("caption"));
final Textbox tb = new Textbox((String) this.propz.get("text"));
tb.onAction(new Callback<ActionEvent>() {
public void call(ActionEvent actionEvent) throws Exception {
propz.put("text",tb.getText());
context.redraw();
}
});