decoration property Null safety

Decoration? decoration

What to paint on the Material.

The decoration is painted at the position and size of the referenceBox, on the Material that owns the controller.

Implementation

Decoration? get decoration => _decoration;
void decoration=(Decoration? value)

Implementation

set decoration(Decoration? value) {
  if (value == _decoration)
    return;
  _decoration = value;
  _painter?.dispose();
  _painter = _decoration?.createBoxPainter(_handleChanged);
  controller.markNeedsPaint();
}