Published: September 04, 2015, Edited by: Mads Hobye

Integrate Java/Swing GUI in your processing sketch

Nikolaj Møbius at Fablab RUC managed to integrate the native Java Swing gui system into a processing sketch. Two windows are opened one for the graphics of processing and one window for the GUI interface. This enables you to create buttons, sliders etc. and have a control panel for your sketch. This is especially a good setup for projection based installation. Here you can run the graphics on the projects and have the control available on e.g. your laptop screen.

You can either handwrite the code that creates the GUI or you can use a graphical tool to design your gui. The simplest tool we could find was GUI Genie.

After designing your interface you go to the build panel and extract the code:

Alternatively Eclipse has a GUI builder integrated as well.

Be aware that it does not implement action listeners. You have to do this yourself. To get you started Nikolaj has made a small example sketch with some basic slider and buttons. Copy paste the code into an empty processing sketch to see it running:

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.event.*;

MyPanel controlPanel;

color paper = color(0);
int ballYPos=0;
int ballWidth=20;
int ballHeight=20;

//**************************************************************
//  Copy-paste from GuiGeene 
//**************************************************************

public class MyPanel extends JPanel {
  private JButton jcomp1;
  private JButton jcomp2;
  private JButton jcomp3;
  private JSlider jcomp4;
  private JSlider jcomp5;
  private JSlider jcomp6;

  public MyPanel() {
    //construct components
    jcomp1 = new JButton ("Click me!");
    jcomp2 = new JButton ("Button 2");
    jcomp3 = new JButton ("Button 3");
    jcomp4 = new JSlider (-100, 100);
    jcomp5 = new JSlider (0, 100);
    jcomp6 = new JSlider (0, 100);

    //-Example: add a action listener to this button:
    jcomp1.addActionListener(new Button1Click());
    //-Example: add a change listener to this slider:
    jcomp4.addChangeListener(new HSlider1Change());
    jcomp5.addChangeListener(new HSlider2Change());
    jcomp6.addChangeListener(new HSlider3Change());



    //set components properties
    jcomp4.setOrientation (JSlider.HORIZONTAL);
    jcomp4.setMinorTickSpacing (10);
    jcomp4.setMajorTickSpacing (50);
    jcomp4.setPaintTicks (true);
    jcomp4.setPaintLabels (true);
    jcomp5.setOrientation (JSlider.HORIZONTAL);
    jcomp5.setMinorTickSpacing (10);
    jcomp5.setMajorTickSpacing (50);
    jcomp5.setPaintTicks (true);
    jcomp5.setPaintLabels (true);
    jcomp6.setOrientation (JSlider.HORIZONTAL);
    jcomp6.setMinorTickSpacing (10);
    jcomp6.setMajorTickSpacing (50);
    jcomp6.setPaintTicks (true);
    jcomp6.setPaintLabels (true);

    //adjust size and set layout
    setPreferredSize (new Dimension (412, 179));
    setLayout (null);

    //add components
    add (jcomp1);
    add (jcomp2);
    add (jcomp3);
    add (jcomp4);
    add (jcomp5);
    add (jcomp6);

    //set component bounds (only needed by Absolute Positioning)
    jcomp1.setBounds (5, 5, 100, 20);
    jcomp2.setBounds (5, 60, 100, 20);
    jcomp3.setBounds (5, 115, 100, 20);
    jcomp4.setBounds (115, 5, 270, 50);
    jcomp5.setBounds (115, 60, 270, 50);
    jcomp6.setBounds (115, 115, 270, 50);
  }

  //-Comment out main by GuiGenee, we set up ourselves:

  /*    public static void main (String[] args) {
   JFrame frame = new JFrame ("MyPanel");
   frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
   frame.getContentPane().add (new MyPanel());
   frame.pack();
   frame.setVisible (true);
   }
   */
}


//**************************************************************
//  This gets called when button is clicked
//**************************************************************

class Button1Click implements ActionListener
{
  public void actionPerformed(ActionEvent e)
  {
    JButton b = (JButton)e.getSource();
    b.setLabel("Thanks!");
    timer=millis()+1000;

    println("Click");
    paper = color(random(255), random(255), random(255));
  }
}

//**************************************************************
//  This gets called when slider is changed
//**************************************************************

class HSlider1Change implements ChangeListener
{
  public void stateChanged(ChangeEvent e)
  {
    JSlider source = (JSlider)e.getSource();
    ballYPos = (int)source.getValue();
  }
}

class HSlider2Change implements ChangeListener
{
  public void stateChanged(ChangeEvent e)
  {
    JSlider source = (JSlider)e.getSource();
    ballWidth = (int)source.getValue();

  }
}

class HSlider3Change implements ChangeListener
{
  public void stateChanged(ChangeEvent e)
  {
    JSlider source = (JSlider)e.getSource();
    ballHeight = (int)source.getValue();

  }
}



//**************************************************************
//  Normal procesing setup
//**************************************************************

void setup()
{
  size(384, 216);
  JFrame frame =new JFrame("Controls");
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

  controlPanel = new MyPanel();
  controlPanel.setOpaque(true); //content panes must be opaque
  frame.setContentPane(controlPanel);

  //Display the window.
  frame.pack();
  frame.setVisible(true);
}

//**************************************************************
//  Normal procesing draw
//**************************************************************

int timer=0;

void draw()
{
  if (timer!=0)
  {
    if (millis()>=timer)
    {
      controlPanel.jcomp1.setLabel("Again!");
      timer=0;
    }
  }

  background(paper);
  ellipse(millis()/10%width, height/2-ballYPos, ballWidth, ballHeight);
}