如何製作透明的JFrame，但保持其他一切？

Question

我想讓JFrame透明，但它上面的圖像是不透明的。這是我現在有：

有誰知道一種方法，使只有JFrame透明？

這裏是我的代碼：

import javax.swing.*; 
import java.awt.*; 
import com.sun.awt.AWTUtilities; 
import static java.awt.GraphicsDevice.WindowTranslucency.*; 

public class SplashDemo extends JFrame 
{ 
    public SplashDemo() 
    { 
     setUndecorated(true); 
     setSize(200, 200); 

     add(new JLabel(new ImageIcon("puppy2.png"))); 
     setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); 
     setVisible(true); 

     setOpacity(0.85f);  
    } 

    public static void main(String[] args) 
    { 
     new SplashDemo(); 
    } 
} 

Answer 1

基本上，你需要做一個透明窗口，半透明的內容窗格。這添加到內容窗格將意味着什麼，將繼續無需額外alphering被渲染...

public class TranscluentWindow { 

    public static void main(String[] args) { 
     new TranscluentWindow(); 
    } 

    public TranscluentWindow() { 
     EventQueue.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       try { 
        try { 
         UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); 
        } catch (Exception ex) { 
        } 

        JWindow frame = new JWindow(); 
        frame.setAlwaysOnTop(true); 
        frame.addMouseListener(new MouseAdapter() { 
         @Override 
         public void mouseClicked(MouseEvent e) { 
          if (e.getClickCount() == 2) { 
           SwingUtilities.getWindowAncestor(e.getComponent()).dispose(); 
          } 
         } 
        }); 
        frame.setBackground(new Color(0,0,0,0)); 
        frame.setContentPane(new TranslucentPane()); 
        frame.add(new JLabel(new ImageIcon(ImageIO.read(getClass().getResource("/Puppy.png"))))); 
        frame.pack(); 
        frame.setLocationRelativeTo(null); 
        frame.setVisible(true); 
       } catch (IOException ex) { 
        ex.printStackTrace(); 
       } 

      } 
     }); 
    } 

    public class TranslucentPane extends JPanel { 

     public TranslucentPane() { 
      setOpaque(false); 
     } 

     @Override 
     protected void paintComponent(Graphics g) { 
      super.paintComponent(g); 

      Graphics2D g2d = (Graphics2D) g.create(); 
      g2d.setComposite(AlphaComposite.SrcOver.derive(0.85f)); 
      g2d.setColor(getBackground()); 
      g2d.fillRect(0, 0, getWidth(), getHeight()); 

     } 

    } 

}