/* * Swing version. */ import javax.swing.*; import javax.swing.border.Border; import javax.swing.event.*; import java.awt.*; import java.awt.event.*; /* * Displays a framed area. When the user clicks within * the area, this program displays a filled rectangle * and a string indicating the coordinates where the * click occurred. */ public class RectangleDemo extends JApplet { JLabel label; //Called only when this is run as an applet. public void init() { buildUI(getContentPane()); } void buildUI(Container container) { container.setLayout(new BoxLayout(container, BoxLayout.Y_AXIS)); RectangleArea rectangleArea = new RectangleArea(this); container.add(rectangleArea); label = new JLabel("Click within the framed area."); container.add(label); //Align the left edges of the components. rectangleArea.setAlignmentX(LEFT_ALIGNMENT); label.setAlignmentX(LEFT_ALIGNMENT); //unnecessary, but doesn't hurt } public void updateLabel(Point point) { label.setText("Click occurred at coordinate (" + point.x + ", " + point.y + ")."); } //Called only when this is run as an application. public static void main(String[] args) { JFrame f = new JFrame("RectangleDemo"); f.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); RectangleDemo controller = new RectangleDemo(); controller.buildUI(f.getContentPane()); f.pack(); f.setVisible(true); } } class RectangleArea extends JPanel { Point point = null; RectangleDemo controller; Dimension preferredSize = new Dimension(300,100); int rectWidth = 50; int rectHeight = 50; public RectangleArea(RectangleDemo controller) { this.controller = controller; Border raisedBevel = BorderFactory.createRaisedBevelBorder(); Border loweredBevel = BorderFactory.createLoweredBevelBorder(); Border compound = BorderFactory.createCompoundBorder (raisedBevel, loweredBevel); setBorder(compound); addMouseListener(new MouseAdapter() { public void mousePressed(MouseEvent e) { int x = e.getX(); int y = e.getY(); if (point == null) { point = new Point(x, y); } else { point.x = x; point.y = y; } repaint(); } }); } public Dimension getPreferredSize() { return preferredSize; } public void paintComponent(Graphics g) { super.paintComponent(g); //paint background //Paint a filled rectangle at user's chosen point. if (point != null) { g.drawRect(point.x, point.y, rectWidth - 1, rectHeight - 1); g.setColor(Color.yellow); g.fillRect(point.x + 1, point.y + 1, rectWidth - 2, rectHeight - 2); controller.updateLabel(point); } } }