je ne vois pas ce qui ne marche pas dans ce programme de démo fourni avec jdk
import java.awt.event.*;
import java.awt.*;
import java.applet.*;
import java.util.Vector;
public class DrawTest extends Applet{
DrawPanel panel;
DrawControls controls;
public void init() {
setLayout(new BorderLayout());
panel = new DrawPanel();
controls = new DrawControls(panel);
add("Center", panel);
add("South",controls);
}
public void destroy() {
remove(panel);
remove(controls);
}
public static void main(String args[]) {
Frame f = new Frame("DrawTest" );
DrawTest drawTest = new DrawTest();
drawTest.init();
drawTest.start();
f.add("Center", drawTest);
f.setSize(300, 300);
f.show();
}
public String getAppletInfo() {
return "A simple drawing program.";
}
}
class DrawPanel extends Panel implements MouseListener, MouseMotionListener {
public static final int LINES = 0;
public static final int POINTS = 1;
int mode = LINES;
Vector lines = new Vector();
Vector colors = new Vector();
int x1,y1;
int x2,y2;
int xl, yl;
public DrawPanel() {
setBackground(Color.white);
addMouseMotionListener(this);
addMouseListener(this);
}
public void setDrawMode(int mode) {
switch (mode) {
case LINES:
case POINTS:
this.mode = mode;
break;
default:
throw new IllegalArgumentException();
}
}
public void mouseDragged(MouseEvent e) {
e.consume();
switch (mode) {
case LINES:
xl = x2;
yl = y2;
x2 = e.getX();
y2 = e.getY();
break;
case POINTS:
default:
colors.addElement(getForeground());
lines.addElement(new Rectangle(x1, y1, e.getX(), e.getY()));
x1 = e.getX();
y1 = e.getY();
break;
}
repaint();
}
public void mouseMoved(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
e.consume();
switch (mode) {
case LINES:
x1 = e.getX();
y1 = e.getY();
x2 = -1;
break;
case POINTS:
default:
colors.addElement(getForeground());
lines.addElement(new Rectangle(e.getX(), e.getY(), -1, -1));
x1 = e.getX();
y1 = e.getY();
repaint();
break;
}
}
public void mouseReleased(MouseEvent e) {
e.consume();
switch (mode) {
case LINES:
colors.addElement(getForeground());
lines.addElement(new Rectangle(x1, y1, e.getX(), e.getY()));
x2 = xl = -1;
break;
case POINTS:
default:
break;
}
repaint();
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public void mouseClicked(MouseEvent e) {
}
public void paint(Graphics g) {
int np = lines.size();
/* draw the current lines */
g.setColor(getForeground());
g.setPaintMode();
for (int i=0; i < np; i++) {
Rectangle p = (Rectangle)lines.elementAt(i);
g.setColor((Color)colors.elementAt(i));
if (p.width != -1) {
g.drawLine(p.x, p.y, p.width, p.height);
} else {
g.drawLine(p.x, p.y, p.x, p.y);
}
}
if (mode == LINES) {
g.setXORMode(getBackground());
if (xl != -1) {
/* erase the last line. */
g.drawLine(x1, y1, xl, yl);
}
g.setColor(getForeground());
g.setPaintMode();
if (x2 != -1) {
g.drawLine(x1, y1, x2, y2);
}
}
}
}
class DrawControls extends Panel implements ItemListener {
DrawPanel target;
public DrawControls(DrawPanel target) {
this.target = target;
setLayout(new FlowLayout());
setBackground(Color.lightGray);
target.setForeground(Color.red);
CheckboxGroup group = new CheckboxGroup();
Checkbox b;
add(b = new Checkbox(null, group, false));
b.addItemListener(this);
b.setBackground(Color.red);
add(b = new Checkbox(null, group, false));
b.addItemListener(this);
b.setBackground(Color.green);
add(b = new Checkbox(null, group, false));
b.addItemListener(this);
b.setBackground(Color.blue);
add(b = new Checkbox(null, group, false));
b.addItemListener(this);
b.setBackground(Color.pink);
add(b = new Checkbox(null, group, false));
b.addItemListener(this);
b.setBackground(Color.orange);
add(b = new Checkbox(null, group, true));
b.addItemListener(this);
b.setBackground(Color.black);
target.setForeground(b.getForeground());
Choice shapes = new Choice();
shapes.addItemListener(this);
shapes.addItem("Lines" );
shapes.addItem("Points" );
shapes.setBackground(Color.lightGray);
add(shapes);
}
public void paint(Graphics g) {
Rectangle r = getBounds();
g.setColor(Color.lightGray);
g.draw3DRect(0, 0, r.width, r.height, false);
}
public void itemStateChanged(ItemEvent e) {
if (e.getSource() instanceof Checkbox) {
target.setForeground(((Component)e.getSource()).getBackground());
} else if (e.getSource() instanceof Choice) {
String choice = (String) e.getItem();
if (choice.equals("Lines" )) {
target.setDrawMode(DrawPanel.LINES);
} else if (choice.equals("Points" )) {
target.setDrawMode(DrawPanel.POINTS);
}
}
}
}