public void mouseDragged(MouseEvent evt) {
Graphics g = canvas.getGraphics();
g.setColor(color);
if (type == 0) {
g.setXORMode(canvas.getBackground());
g.drawRect(start.x, start.y, end.x - start.x, end.y - start.y);
end = evt.getPoint();
g.drawRect(start.x, start.y, end.x - start.x, end.y - start.y);
} else if (type == 1) {
int radius;
g.setXORMode(canvas.getBackground());
radius = (int) Math.sqrt(Math.pow(end.x - start.x, 2) + Math.pow(end.y - start.y, 2));
g.drawOval(start.x - radius, start.y - radius, 2 * radius, 2 * radius);
end = evt.getPoint();
radius = (int) Math.sqrt(Math.pow(end.x - start.x, 2) + Math.pow(end.y - start.y, 2));
g.drawOval(start.x - radius, start.y - radius, 2 * radius, 2 * radius);
} else if (type == 2) {
g.setXORMode(canvas.getBackground());
g.drawOval(start.x, start.y, end.x - start.x, end.y - start.y);
end = evt.getPoint();
g.drawOval(start.x, start.y, end.x - start.x, end.y - start.y);
}
}
public void mouseReleased(MouseEvent evt) {
Graphics g = canvas.getGraphics();
g.setColor(color);
g.setPaintMode();
end = evt.getPoint();
if (type == 0) {
g.drawRect(start.x, start.y, end.x - start.x, end.y - start.y);
if (filled.getState() == true) g.fillRect(start.x, start.y, end.x - start.x, end.y - start.y);
status.setText("2. Ecke des Rechtecks festgelegt");
} else if (type == 1) {
int radius;
radius = (int) Math.sqrt(Math.pow(end.x - start.x, 2) + Math.pow(end.y - start.y, 2));
g.drawOval(start.x - radius, start.y - radius, 2 * radius, 2 * radius);
if (filled.getState() == true)
g.fillOval(start.x - radius, start.y - radius, 2 * radius, 2 * radius);
status.setText("Radius des Kreises festgelegt");
} else if (type == 2) {
g.drawOval(start.x, start.y, end.x - start.x, end.y - start.y);
if (filled.getState() == true) g.fillOval(start.x, start.y, end.x - start.x, end.y - start.y);
status.setText("Radius der Ellipse festgelegt");
}
}
public void init() {
status = new Label("", Label.CENTER);
menu = new Panel();
canvas = new MyCanvas();
farbe = new Choice();
color = Color.blue;
filled = new Checkbox("ausgefuellt");
namen = new String[] {"Rechteck", "Kreis", "Ellipse"};
farben = new String[] {"blau", "gelb", "gruen", "rot", "schwarz", "weiss"};
button = new Button[namen.length];
type = -1;
for (int i = 0; i < namen.length; i++) {
button[i] = new Button(namen[i]);
button[i].addActionListener(this);
menu.add(button[i]);
}
for (int i = 0; i < farben.length; i++) farbe.add(farben[i]);
filled.addItemListener(this);
farbe.addItemListener(this);
canvas.addMouseListener(this);
canvas.addMouseMotionListener(this);
menu.add(filled);
menu.add(farbe);
setLayout(new BorderLayout());
setBackground(Color.lightGray);
add(menu, "North");
add(canvas, "Center");
add(status, "South");
}