Currently supported instruction set:
    CPCL
    TSPL

...' var control = ControlBase.create(demoXml); var jsonData = json.decode(dataSource); control.setDataSource(DataSource(jsonData)); control.performLayout(PrinterConstraints(maxWidth: 837)); CPCLCanvas canvas = CPCLCanvas(); canvas.pageSize = control.actualSize; canvas.reset(); control.paint(canvas, PrinterOffset.zero); canvas.end(); io.send(canvas.toCommand()); // output instruction ">

    final demoXml = '
   
    ...
   '
    var control = ControlBase.create(demoXml);

    var jsonData = json.decode(dataSource);

    control.setDataSource(DataSource(jsonData));

    control.performLayout(PrinterConstraints(maxWidth: 837));
    CPCLCanvas canvas = CPCLCanvas();
    canvas.pageSize = control.actualSize;
    canvas.reset();

    control.paint(canvas, PrinterOffset.zero);

    canvas.end();

    io.send(canvas.toCommand()); // output instruction

...' control = ControlBase.create(demoXml); } @override Widget build(BuildContext context) { return PreviewWidget( control: control ); } ">

    ControlBase control;
    @override
    void initState() {
        super.initState();
        final demoXml = '
   
    ...
   '
        control = ControlBase.create(demoXml);
    }

    @override
    Widget build(BuildContext context) {
        return PreviewWidget(
            control: control
        );
    }