import java.awt.*; import java.awt.event.*; import javax.swing.*; public class PaintBox extends JFrame { private SlidePanel colorChooser; private JPanel colorView; private TopButtonPanel topPanel; private PaintPanel paintArea; /* the constructor */ public PaintBox() { firstInit(); init(); } private void init() { // a helper method Container pane = getContentPane(); /* the color chooser panel at the east side */ JPanel eastPanel = new JPanel(); /* A layout manager of the more complex kind */ GridBagLayout gbl = new GridBagLayout(); eastPanel.setLayout(gbl); GridBagConstraints gbc = new GridBagConstraints(); colorChooser = new SlidePanel(this); gbc.gridx = 0; // first column gbc.gridy = 0; // first row eastPanel.add(colorChooser, gbc); colorView = new JPanel(); colorView.setBackground(Color.black); gbc.gridx = 0; // first column gbc.gridy = 1; // second row gbc.ipadx = 90; gbc.ipady = 90; eastPanel.add(colorView, gbc); pane.add(eastPanel, "East"); /* the buttons at the top */ topPanel = new TopButtonPanel(this); pane.add(topPanel, "North"); /* the main paint area */ paintArea = new PaintPanel(); pane.add(paintArea, "Center"); } public void setColor(int r, int g, int b) { colorView.setBackground(new Color(r, g, b)); paintArea.setColor(new Color(r, g, b)); } public void setFilled(boolean b) { paintArea.setFilled(b); } public void setShape(int i) { paintArea.setShape(i); } /* A common GUI constructor helper method */ private void firstInit() { addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); setTitle("PaintBox"); setSize(600,400); /* Find the middle position on the screen */ Dimension dim = Toolkit.getDefaultToolkit(). getScreenSize(); int w = (dim.width - 600) / 2; int h = (dim.height -300) / 2; if (w < 0 || h < 0) { w = 0; h = 0; } setLocation(w, h); } public static void main(String[] arg) { PaintBox p = new PaintBox(); p.show(); } }