This reference is for Processing 2.0+. If you have a previous version, use the reference included with your software. If you see any errors or have suggestions, please let us know. If you prefer a more technical reference, visit the Processing Javadoc.

Name | ### mouseButton
Examples |
    // Click within the image and press
    // the left and right mouse buttons to
    // change the value of the rectangle
    void draw() {
      if (mousePressed && (mouseButton == LEFT)) {
        fill(0);
      } else if (mousePressed && (mouseButton == RIGHT)) {
        fill(255);
      } else {
        fill(126);
      }
      rect(25, 25, 50, 50);
    }
    // Click within the image and press
    // the left and right mouse buttons to
    // change the value of the rectangle
    void draw() {
      rect(25, 25, 50, 50);
    }

    void mousePressed() {
      if (mouseButton == LEFT) {
        fill(0);
      } else if (mouseButton == RIGHT) {
        fill(255);
      } else {
        fill(126);
      }
    }
Description | Processing automatically tracks if the mouse button is pressed and which button is pressed. The value of the system variable mouseButton is either LEFT, RIGHT, or CENTER depending on which button is pressed.
Related | mouseX mouseY mousePressed mouseReleased() mouseMoved() mouseDragged()

Updated on October 26, 2013 08:58:32pm PDT