Hello I am trying to create a Java game and need to add some effects to my label. I have the following questions
You can use a AlphaComposite to change the opactiy level of a component...
Now, with a little clever use of a timer, you can make the label fade in and out or simply control the opacity as you please...
public class TestFadeLabel { public static void main(String[] args) { new TestFadeLabel(); } public TestFadeLabel() { EventQueue.invokeLater(new Runnable() { @Override public void run() { try { UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); } catch (ClassNotFoundException ex) { } catch (InstantiationException ex) { } catch (IllegalAccessException ex) { } catch (UnsupportedLookAndFeelException ex) { } JFrame frame = new JFrame("Testing"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setLayout(new BorderLayout()); frame.add(new MainPane()); frame.pack(); frame.setLocationRelativeTo(null); frame.setVisible(true); } }); } public class MainPane extends JPanel { private float direction = -0.05f; private FadeLabel label = new FadeLabel(); public MainPane() { setLayout(new BorderLayout()); JLabel background = new JLabel(); background.setLayout(new GridBagLayout()); try { background.setIcon(new ImageIcon(ImageIO.read(getClass().getResource("/Storm.jpg")))); } catch (Exception e) { e.printStackTrace(); } add(background); label = new FadeLabel(); background.add(label); Timer timer = new Timer(100, new ActionListener() { @Override public void actionPerformed(ActionEvent e) { float alpha = label.getAlpha(); alpha += direction; if (alpha < 0) { alpha = 0; direction = 0.05f; } else if (alpha > 1) { alpha = 1; direction = -0.05f; } label.setAlpha(alpha); } }); timer.setRepeats(true); timer.setCoalesce(true); timer.start(); } } public class FadeLabel extends JLabel { private float alpha; private BufferedImage background; public FadeLabel() { try { background = ImageIO.read(getClass().getResource("/Cloud.png")); } catch (Exception e) { } setText("Hide and go seek"); setHorizontalAlignment(CENTER); setVerticalAlignment(CENTER); setAlpha(1f); } public void setAlpha(float value) { if (alpha != value) { float old = alpha; alpha = value; firePropertyChange("alpha", old, alpha); repaint(); } } public float getAlpha() { return alpha; } @Override public Dimension getPreferredSize() { return background == null ? super.getPreferredSize() : new Dimension(background.getWidth(), background.getHeight()); } @Override public void paint(Graphics g) { // This is one of the few times I would directly override paint // This makes sure that the entire paint chain is now using // the alpha composite, including borders and child components Graphics2D g2d = (Graphics2D) g.create(); g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, getAlpha())); super.paint(g2d); g2d.dispose(); } @Override protected void paintComponent(Graphics g) { // This is one of the few times that doing this before the super call // will work... if (background != null) { int x = (getWidth() - background.getWidth()) / 2; int y = (getHeight() - background.getHeight()) / 2; g.drawImage(background, x, y, this); } super.paintComponent(g); } } }