selectingBrush property
      
      Brush
      get
      selectingBrush
      
    
    
    
Implementation
Brush get selectingBrush => _selectingBrush;
      
      set
      selectingBrush
      (Brush newValue) 
      
    
    
    
Implementation
set selectingBrush(Brush newValue) {
  _selectingBrush = newValue;
  _controller.update();
}