动态设置不同的jtree行高

时间:2015-08-17 16:42:52

标签: java swing jtree jtreetable treecellrenderer

所有

最近两天试图为JTree动态设置不同的行高,但是没有成功。下面是我想要实现的目标......以下是我的尝试:

(1)使用setRowHeight(0),以便节点查询它的当前单元格渲染器

(2)设置从jtree的单元格渲染器返回的组件的PreferredSize(Dimension d)。

(3)更改渲染器本身的rowheight,我现在理解不应该这样做。

我不知道如何在同一列上设置不同的单元格渲染器,例如下面的列A,也许我可以硬编码不同的行高。

enter image description here

任何人都有任何提示或技巧,或者更好的仍然是一个有效的例子,我的脑子被炸了,我似乎已经筋疲力尽了所有其他资源......这应该是可能的,对吗?

1 个答案:

答案 0 :(得分:2)

(1)(2)使用JDK1.8.0_51上的Windows 10可以正常使用我:

enter image description here

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

public class RowHeightsDynamicallyTest {
  public JComponent makeUI() {
    JTree tree = new JTree() {
      @Override public void updateUI() {
        setCellRenderer(null);
        super.updateUI();
        setCellRenderer(new RowHeightsDynamicallyRenderer());
        setRowHeight(0);
        setRootVisible(false);
        setShowsRootHandles(false);
      }
    };
    return new JScrollPane(tree);
  }
  public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
      @Override 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 (ClassNotFoundException | InstantiationException
               | IllegalAccessException | UnsupportedLookAndFeelException ex) {
      ex.printStackTrace();
    }
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    f.getContentPane().add(new RowHeightsDynamicallyTest().makeUI());
    f.setSize(320, 240);
    f.setLocationRelativeTo(null);
    f.setVisible(true);
  }
}

class RowHeightsDynamicallyRenderer extends DefaultTreeCellRenderer {
  private int height;
  @Override public Component getTreeCellRendererComponent(
      JTree tree, Object value, boolean selected,
      boolean expanded, boolean leaf, int row, boolean hasFocus) {
    JLabel l = (JLabel) super.getTreeCellRendererComponent(
        tree, value, selected, expanded, leaf, row, hasFocus);
    l.setFont(tree.getFont().deriveFont(leaf ? 16f : 48f));

    height = leaf ? 20 : 60;
    //use dummy height Icon: l.setIcon(new DummyHeightIcon(height));
    //use <td> height: l.setText(String.format("<html><table><tr><td height='%d'>%s", height, value));
    return l;
  }
  @Override public Dimension getPreferredSize() {
    Dimension d = super.getPreferredSize();
    d.height = height;
    return d;
  }
}

// class DummyHeightIcon implements Icon {
//   private final int height;
//   public DummyHeightIcon(int height) {
//     this.height = height;
//   }
//   @Override public void paintIcon(Component c, Graphics g, int x, int y) {}
//   @Override public int getIconWidth() {
//     return 0;
//   }
//   @Override public int getIconHeight() {
//     return height;
//   }
// }