Related: Flutter based fml.dev.

Example:

    <FML version="1.0" title="Counter-Page">
         <HEADER height="46" color="blue">
              <CENTER>
                    <TEXT value="FML Demo Home Page" size="20" color="white"/>
              </CENTER>
         </HEADER>
         <CENTER>
              <COL center="true">
                   <TEXT value="You have pushed the button this many times:" color="#7c7c7c"/>
                   <TEXT id="clicknumber" value="0" style="h3" color="#7c7c7c"/>
              </COL>
         </CENTER>
         <POS bottom="10" right="10">
              <BTN onclick="clicknumber.set({clicknumber} + 1);" width="40" height="40" radius="50" color="blue" type="elevated">
                   <ICON icon="add" color="white"/>
              </BTN>
         </POS>
    </FML>