无法拖动来调整JTable列的大小

Question

长话短说，我正在制作一个自定义Swing组件，它基本上是一个JTable，其侧面板是面板。该表当然应该是可滚动的，并且有一个表头，但是由于我只希望头部位于实际的JTable之上而不是在侧面面板之上，所以我不得不抽出一些技巧使其工作。但那部分工作正常。

不过，在这个过程中，我设法打破了JTableHeader的鼠标拖动列调整功能。对于为什么以及我能做些什么，我完全无能为力。

下面是一个最小的工作示例来说明我的问题。

import java.awt.Dimension; 
import java.awt.Rectangle; 
import java.awt.event.ComponentAdapter; 
import java.awt.event.ComponentEvent; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.JViewport; 
import javax.swing.Scrollable; 
import javax.swing.table.JTableHeader; 


final class FooTable extends JPanel implements Scrollable { 

    public FooTable() { 
     initComponents(); 
    } 

    // Generated by NetBeans IDE 
    @SuppressWarnings("unchecked") 
    // <editor-fold defaultstate="collapsed" desc="Generated Code"> 
    private void initComponents() { 
     java.awt.GridBagConstraints gridBagConstraints; 

     sidePanel = new javax.swing.JPanel(); 
     table = new javax.swing.JTable(); 

     setLayout(new java.awt.GridBagLayout()); 

     sidePanel.setMinimumSize(new java.awt.Dimension(70, 0)); 
     sidePanel.setPreferredSize(new java.awt.Dimension(70, 0)); 
     sidePanel.setLayout(null); 
     gridBagConstraints = new java.awt.GridBagConstraints(); 
     gridBagConstraints.gridx = 0; 
     gridBagConstraints.gridy = 0; 
     gridBagConstraints.fill = java.awt.GridBagConstraints.BOTH; 
     gridBagConstraints.anchor = java.awt.GridBagConstraints.NORTHWEST; 
     gridBagConstraints.weighty = 1.0; 
     add(sidePanel, gridBagConstraints); 

     table.setFont(table.getFont().deriveFont(table.getFont().getSize()+1f)); 
     table.setModel(new javax.swing.table.DefaultTableModel(
      new Object [][] { 
       {"1", "A", "I", "-"}, 
       {"2", "B", "II", "--"}, 
       {"3", "C", "III", "---"}, 
       {"4", "D", "IV", "----"}, 
       {"5", "E", "V", "-----"}, 
       {"6", "F", "VI", "------"}, 
       {"7", "G", "VII", "-------"}, 
       {"8", "H", "VIII", "--------"}, 
       {"9", "I", "IX", "---------"}, 
       {"10", "J", "X", "----------"} 
      }, 
      new String [] { 
       "Column 1", "Column 2", "Column 3", "Column 4" 
      } 
     )); 
     table.setRowHeight(24); 
     table.setSelectionMode(javax.swing.ListSelectionModel.MULTIPLE_INTERVAL_SELECTION); 
     gridBagConstraints = new java.awt.GridBagConstraints(); 
     gridBagConstraints.gridx = 1; 
     gridBagConstraints.gridy = 0; 
     gridBagConstraints.fill = java.awt.GridBagConstraints.BOTH; 
     gridBagConstraints.anchor = java.awt.GridBagConstraints.NORTHWEST; 
     gridBagConstraints.weightx = 1.0; 
     add(table, gridBagConstraints); 
    }// </editor-fold> 

    public JScrollPane createScrollView() { 
     JScrollPane jsp = new JScrollPane(this); 
     JViewport jvp = new JViewport(); 
     final JTableHeader th = new JTableHeader(); 

     th.setTable(table); 
     th.setColumnModel(table.getColumnModel()); 
     th.setResizingAllowed(true); 

     jvp.setView(new JPanel() { 

      { 
       setLayout(null); 
       add(th); 

       th.setLocation(70, 0); 

       FooTable.this.addComponentListener(new ComponentAdapter() { 

        @Override 
        public void componentResized(ComponentEvent e) { 
         th.setSize(FooTable.this.getWidth(), th.getPreferredSize().height); 
        } 
       }); 
       setPreferredSize(new Dimension(th.getPreferredSize().width, th.getPreferredSize().height)); 
      } 
     }); 
     jsp.setColumnHeader(jvp); 
     return jsp; 
    } 

    // Variables declaration - do not modify 
    private javax.swing.JPanel sidePanel; 
    private javax.swing.JTable table; 
    // End of variables declaration 


    // 
    // Scrollable implementation 
    // 
    public Dimension getPreferredScrollableViewportSize() { 
     Dimension d = new Dimension(); 
     d.width = sidePanel.getPreferredSize().width + table.getPreferredSize().width; 
     d.height = sidePanel.getPreferredSize().height + table.getPreferredSize().height; 
     return d; 
    } 

    public int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction) { 
     return table.getScrollableUnitIncrement(visibleRect, orientation, direction); 
    } 

    public int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction) { 
     return table.getScrollableBlockIncrement(visibleRect, orientation, direction); 
    } 

    public boolean getScrollableTracksViewportWidth() { 
     return table.getScrollableTracksViewportWidth(); 
    } 

    public boolean getScrollableTracksViewportHeight() { 
     return table.getScrollableTracksViewportHeight(); 
    } 

    // 
    // Test program 
    // 
    public static void main(String[] args) { 
     JFrame f = new JFrame(); 
     f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     FooTable fooTable = new FooTable(); 
     f.add(fooTable.createScrollView()); 
     f.pack(); 
     f.setVisible(true); 
    } 

} 

Answer 1

我想你错过了什么，也告诉JTable有关JTableHeader。在该方法中createScrollView尝试添加以下只是返回前：

table.setTableHeader(th);