java - 使用 Numbus L&F 设置 JTree 选择背景

Question

如何在使用 Nimbus L&F 时为 JTree 中的选定项目设置背景颜色？

类似问题的旧答案中的建议对 Nimbus 不起作用，所以我尝试:

final UIDefaults def = new UIDefaults();
def.put( "Tree.background", Color.LIGHT_GRAY );
def.put( "Tree.selectionBackground", Color.RED );
def.put( "Tree.drawHorizontalLines", true );
def.put( "Tree.drawVerticalLines", true );
def.put( "Tree.leftChildIndent", 12 );
def.put( "Tree.rightChildIndent", 12 );
myTree.putClientProperty( "Nimbus.Overrides", def );
myTree.putClientProperty( "Nimbus.Overrides.InheritDefaults", false );

这适用于背景、drawHorizo​​ntalLines、drawVerticalLines、leftChildIndent 和 rightChildIndent，但无法执行任何操作用于选择背景。

我还尝试为“Tree.textForeground”、“Tree.foreground”和“Tree.textBackground”设置各种颜色，但这些都没有效果。

我也试过:

 final Painter<JComponent> painter = new Painter<JComponent>() {
    @Override
    public void paint( final Graphics2D g, final JComponent c, final int w, final int h ) {
       g.setRenderingHint( RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON );
       g.setColor( Color.RED );
       g.fillRect( 0, 0, w, h );
    }
 };
 def.put( "Tree:TreeCell[Enabled+Selected].backgroundPainter", painter );

这也没有效果。

Answer 1

Tree:TreeCell[Enabled+Selected].backgroundPainter 在 Windows 10 上使用 JDK1.8.0_66 对我来说效果很好。

import java.awt.*;
import javax.swing.*;
import javax.swing.Painter;

public class TreeCellPainterTest {
  public JComponent makeUI() {
    //UIDefaults d = new UIDefaults();
    UIDefaults d = UIManager.getLookAndFeelDefaults();
    d.put("Tree:TreeCell[Enabled+Selected].backgroundPainter", new Painter<JComponent>() {
      @Override public void paint(Graphics2D g, JComponent c, int w, int h) {
        g.setColor(Color.GREEN);
        g.fillRoundRect(0, 0, w - 1, h - 1, 15, 15);
      }
    });
    d.put("Tree:TreeCell[Focused+Selected].backgroundPainter", new Painter<JComponent>() {
      @Override public void paint(Graphics2D g, JComponent c, int w, int h) {
        g.setColor(Color.RED);
        g.fillRect(0, 0, w, h);
      }
    });

    JTree tree = new JTree();
    tree.putClientProperty("Nimbus.Overrides", d);
    tree.putClientProperty("Nimbus.Overrides.InheritDefaults", false);

    JPanel p = new JPanel(new GridLayout(1, 2));
    p.add(new JScrollPane(new JTree()));
    p.add(new JScrollPane(tree));
    return p;
  }
  public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
  public static void createAndShowGUI() {
    try {
      for (UIManager.LookAndFeelInfo laf : UIManager.getInstalledLookAndFeels()) {
        if ("Nimbus".equals(laf.getName())) {
          UIManager.setLookAndFeel(laf.getClassName());
        }
      }
    } catch (Exception e) {
      e.printStackTrace();
    }
    JFrame frame = new JFrame();
    frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    frame.getContentPane().add(new TreeCellPainterTest().makeUI());
    frame.setSize(320, 240);
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);
  }
}