강조 표시 방법 (투명 오버레이를 시각적으로 선택, 그립니다) JPanel?

Question

많은 스윙 구성 요소는 JPanel으로 만들어져 있습니다. 때로는 이러한 구성 요소를 선택할 수 있어야합니다.

JPanel을 어떻게 선택 할 수 있습니까? 메뉴 항목과 같은 다른 항목, 또는 JTable 셀처럼 선택해야합니다. 나는. 전체 JPanel은 투명한 파란색으로 덮여 있어야합니다. L/F/테마의 다른 항목과 정확하게 일치한다면 우수 할 것입니다.

가능합니까?

Answer 1

JXLayer/JLayer을 살펴보면 구성 요소 상단에 오버레이를 칠할 수 있습니다.

import java.awt.AlphaComposite; 
import java.awt.Dimension; 
import java.awt.EventQueue; 
import java.awt.Graphics2D; 
import java.awt.GridBagLayout; 
import java.awt.RenderingHints; 
import java.awt.event.MouseAdapter; 
import java.awt.event.MouseEvent; 
import java.util.Map; 
import javax.swing.JFrame; 
import javax.swing.JLabel; 
import javax.swing.JPanel; 
import javax.swing.UIManager; 
import javax.swing.UnsupportedLookAndFeelException; 
import org.jdesktop.jxlayer.JXLayer; 
import org.jdesktop.jxlayer.QualityHints; 
import org.jdesktop.jxlayer.plaf.AbstractBufferedLayerUI; 

public class Test { 

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

    public Test() { 
     EventQueue.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       try { 
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); 
       } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) { 
        ex.printStackTrace(); 
       } 

       SelectablePane pane = new SelectablePane(); 
       SelectableUI ui = new SelectableUI(); 
       JXLayer<JPanel> layer = new JXLayer<>(pane, ui); 
       layer.addMouseListener(new MouseAdapter() { 

        @Override 
        public void mouseClicked(MouseEvent e) { 
         ui.setSelected(!ui.isSelected()); 
        } 

       }); 

       JFrame frame = new JFrame("Testing"); 
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
       frame.add(layer); 
       frame.pack(); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
      } 
     }); 
    } 

    public class SelectablePane extends JPanel { 

     public SelectablePane() { 

      setLayout(new GridBagLayout()); 
      add(new JLabel("Hello world")); 

     } 

     @Override 
     public Dimension getPreferredSize() { 
      return new Dimension(200, 200); 
     } 
    } 

    public static class SelectableUI extends AbstractBufferedLayerUI<JPanel> { 

     public static Map<RenderingHints.Key, Object> mapRenderHints = new QualityHints(); 

     private boolean selected = false; 

     public SelectableUI() { 

      mapRenderHints.put(RenderingHints.KEY_ALPHA_INTERPOLATION, RenderingHints.VALUE_ALPHA_INTERPOLATION_QUALITY); // okay 
      mapRenderHints.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); // bad 
      mapRenderHints.put(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY); // okay 
      mapRenderHints.put(RenderingHints.KEY_DITHERING, RenderingHints.VALUE_DITHER_ENABLE); 
      mapRenderHints.put(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON); 
      mapRenderHints.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR); 
      mapRenderHints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY); 

     } 

     public void setSelected(boolean value) { 

      if (selected != value) { 
       selected = value; 
       firePropertyChange("selected", !selected, selected); 
       repaint(); 
      } 

     } 

     public boolean isSelected() { 
      return selected; 
     } 

     @Override 
     protected void paintLayer(Graphics2D g2, JXLayer<? extends JPanel> l) { 
      super.paintLayer(g2, l); 
      if (isSelected()) { 
       Graphics2D g2d = (Graphics2D) g2.create(); 
       g2d.setColor(UIManager.getColor("List.selectionBackground")); 
       g2d.setComposite(AlphaComposite.SrcOver.derive(0.5f)); 
       g2d.fillRect(0, 0, l.getWidth(), l.getHeight()); 
       g2d.dispose(); 
      } 
     } 

     @Override 
     protected Map<RenderingHints.Key, Object> getRenderingHints(JXLayer<? extends JPanel> l) { 
      return mapRenderHints; 
     } 

     public void repaint() { 
      setDirty(true); 
     } 

     public void invalidate() { 
      setDirty(true); 
     } 

     public void revalidate() { 
      setDirty(true); 
     } 
    } 

}