ty(
      'progress',
      progress,
      showName: false,
      ifNull: '&lt;indeterminate&gt;',
    ));

    // Most text fields have maxLines set to 1.
    properties.add(IntProperty('maxLines', maxLines, defaultValue: 1));

    // Specify the unit as otherwise it would be unclear that time is in
    // milliseconds.
    properties.add(IntProperty('duration', duration.inMilliseconds, unit: 'ms'));

    // Tooltip is used instead of unit for this case as a unit should be a
    // terse description appro