如何在 JTable 行中自动换行

Question

我有一个简单的 JTable，它显示了另一个 JTable 中一行的详细信息（以列格式）。这很好用。但是，有时一行中的文本很长，因此用户最终不得不滚动浏览其中不整洁的内容。

如何将文本换行并允许更改行高以显示其中的所有文本。

代码如下：

 table.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
            @Override
            public void valueChanged(ListSelectionEvent e) {
                if (!e.getValueIsAdjusting()) {
                    int selectedRow = table.getSelectedRow();
                    DefaultTableModel newModel = new DefaultTableModel();
                    String rowName = "Row: " + selectedRow;
                    newModel.setColumnIdentifiers(new Object[]{rowName});
                    for (int i = 0; i < table.getModel().getColumnCount(); i++) {
                        newModel.addRow(new Object[]{table.getModel().getValueAt(selectedRow, i)});
                    }
                    JTable newTable = new JTable(newModel) {
                        /**
                         * 
                         */
                        private static final long serialVersionUID = 1L;

                        @Override
                        public Dimension getPreferredScrollableViewportSize() {
                            return new Dimension(140, 240);
                        }
                    };
                    newTable.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
                    newTable.setRowHeight(14, 30);
                    TableColumnAdjuster tcanewTable = new TableColumnAdjuster(newTable);        
                    tcanewTable.setColumnHeaderIncluded(true);
                    tcanewTable.setColumnDataIncluded(true);
                    tcanewTable.setOnlyAdjustLarger( true );
                    tcanewTable.setDynamicAdjustment( true );
                    tcanewTable.adjustColumns();

                    // Apply any custom renderers and editors
                    JOptionPane.showMessageDialog(frame, new JScrollPane(newTable),
                        rowName, JOptionPane.PLAIN_MESSAGE);
                }
            }
        });

Answer 1

您可以通过将JTextArea 用作表中该列的TableCellRenderer 来完成此操作。例如：

static class WordWrapCellRenderer extends JTextArea implements TableCellRenderer {
    WordWrapCellRenderer() {
        setLineWrap(true);
        setWrapStyleWord(true);
    }

    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
        setText(value.toString());
        setSize(table.getColumnModel().getColumn(column).getWidth(), getPreferredSize().height);
        if (table.getRowHeight(row) != getPreferredSize().height) {
            table.setRowHeight(row, getPreferredSize().height);
        }
        return this;
    }
}

在表中使用WordWrapCellRenderer：

table.getColumnModel().getColumn(columnIndex).setCellRenderer(new WordWrapCellRenderer());

Answer 2

这是已接受答案的更新。

它通过限制getPreferredSize() 调用的数量来提高渲染器的效率。

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

/**
 *  The WordWrapRenderer can be used as a renderer for a JTable column. It will
 *  allow the text to wrap to a new line and adjust the table row height.
 *
 *  Note. This renderer can only be used for a single column in the table.
 */
public class WordWrapRenderer extends JTextArea implements TableCellRenderer
{
    WordWrapRenderer()
    {
        setLineWrap(true);
        setWrapStyleWord(true);
    }

    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column)
    {
        setText( (value == null) ? "" : value.toString() );
        setSize(table.getColumnModel().getColumn(column).getWidth(), table.getRowHeight(row));

        //  Recalculate the preferred height now that the text and renderer width have been set.

        int preferredHeight = getPreferredSize().height;

        if (table.getRowHeight(row) != preferredHeight)
        {
            table.setRowHeight(row, preferredHeight);
        }

        return this;
    }

    private static void createAndShowGUI()
    {
        JTable table = new JTable(2, 3);
        table.setValueAt("A", 0, 0);
        table.setValueAt("This text should wrap by default", 0, 1);

        table.getColumnModel().getColumn(1).setCellRenderer( new WordWrapRenderer() );

        JFrame frame = new JFrame("TableBasic");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add( new JScrollPane( table ) );
        frame.pack();
        frame.setLocationRelativeTo( null );
        frame.setVisible( true );
    }

    public static void main(String[] args)
    {
        java.awt.EventQueue.invokeLater( () -> createAndShowGUI() );
    }
}