TransferMode transferMode

The TransferMode to use when applying the shader to the child.

The default, TransferMode.modulate, is useful for applying an alpha blend to the child. Other transfer modes can be used to create other effects.

Source 

TransferMode get transferMode => _transferMode;
void transferMode=(TransferMode newTransferMode)

Source 

set transferMode (TransferMode newTransferMode) {
  assert(newTransferMode != null);
  if (_transferMode == newTransferMode)
    return;
  _transferMode = newTransferMode;
  markNeedsPaint();
}