| Method signature | Return type | 
                    
                        | canvas | DrawingCanvas | 
                    
                        | canvas holds graphic objects on screen | 
                    
                        | onMouseClick(mouse:Point) | Done | 
                    
                        | Respond to a mouse click (press and release) in the canvas at the given point. | 
                    
                        | onMouseDrag(mouse:Point) | Done | 
                    
                        | Respond to a mouse drag (move during press) in the canvas at the given point. | 
                    
                        | onMouseEnter(mouse:Point) | Done | 
                    
                        | Respond to a mouse entering the canvas at the given point. | 
                    
                        | onMouseExit(mouse:Point) | Done | 
                    
                        | Respond to a mouse exiting the canvas at the given point. | 
                    
                        | onMouseMove(mouse:Point) | Done | 
                    
                        | Respond to a mouse move in the canvas at the given point. | 
                    
                        | onMousePress(mouse:Point) | Done | 
                    
                        | Respond to a mouse press in the canvas at the given point. | 
                    
                        | onMouseRelease(mouse:Point) | Done | 
                    
                        | Respond to a mouse release in the canvas at the given point. | 
                    
                        | startGraphics | Done | 
                    
                        | must be invoked to create window and its contents as well as prepare the window to handle mouse events |