This notify member is called when an event is triggered from any event that this handler has been added to.
"mouseEventHandler_var" is a variable referencing a MouseEventHandler object. | 
        
"mouseEventHandler_var" is a variable referencing a MouseEventHandler object. | 
        
| Name | Type | Description | 
| eventArgs | MouseEventArgs | The arguments object with details about this event and the firing MouseEvent. |