Workshop: Java Mouse and Drawing

• Draw something where the mouse clicks

  • Can't just draw...

  • Need to save mouse coords somewhere, then repaint()

  • Note previous drawing will be erased automatically

• Keep all the items you have drawn

  • Requires saving them in your own data structure

• Optional: Use a cooler data structure

  import java.util.*;
  ...
  ArrayList<Point> points = new ArrayList<Point>();
  ...
  points.add (event.getPoint());
  repaint ();
  ...
  for (Point p : points) {
          g.draw (something at p.x, p.y)
  }
  

• Optional: Draw a path that follows mouse dragging

  • requires MouseMotionListener

  • Usually also your own state variable to remember if mouse is up or down

  • Or could use mouseDragged vs mouseMoved