@Override
			public void actionPerformed(ActionEvent arg0) {

				//it means there is nothing to reDo  
				//warn user in case of user wants to make undo operation
				if(model.getObjects().size()==0 || model.getDraw_index()==model.getObjects().size()){
					JOptionPane.showMessageDialog(null,"You can't do redo operation");
				}
				else{//tell controller to start reDo operation
					paint_panel.clear(); //clear current graph
					control.reDoShape(paint_panel.getG2());
				}
			}