JTable组件中的绘制器和编辑器

JTable填充模型有两种方式，一种是构造JTable时指定行数组和列名数组，这种方式数据会以字符串的形式显示在表格中，因为模型得到的所有列的类型都为String。另一种方式是用TableModel填充表格。应该覆盖getColumnClass方法让模型得到每一列的正确类型。此时值为boolean类型的单元格会绘制为JCheckBox，String类型的值会绘制为JLabel(默认绘制器)。如果有其他类型的值，如Color，还是会绘制为JLabel，因为Color没有默认的绘制器。如果想以自己的形式绘制Color，需要定制自己的绘制器。JTable类中有一个Hashtable用来保存所有的类型和绘制器的关联，调用JTable的setDefaultRenderer方法可以将类型和默认绘制器关联。绘制器是一个实现了TableCellRenderer接口的对象，该接口只有一个方法 public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column)。当单元格需要绘制时就会使用这个方法的返回值绘制单元格。如果想绘制Color类型的数据可以在这个方法中返回一个带颜色的面板。

自定义绘制器代码：

package com.swing.table;import java.awt.BorderLayout;import java.awt.Color;import java.awt.Component;import java.awt.EventQueue;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import java.util.EventObject;import javax.swing.AbstractCellEditor;import javax.swing.JButton;import javax.swing.JColorChooser;import javax.swing.JDialog;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTable;import javax.swing.UIManager;import javax.swing.table.AbstractTableModel;import javax.swing.table.TableCellEditor;import javax.swing.table.TableCellRenderer;import javax.swing.table.TableModel;import com.swing.base.SuperFrame;/** * This program demonstrates how to show a simple table * @version 1.11 2007-08-01 * @author Cay Horstmann */public class TableTest {public static void main(String[] args) {EventQueue.invokeLater(new Runnable() {public void run() {JFrame frame = new PlanetTableFrame();frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.setVisible(true);}});}}/** * This frame contains a table of planet data. */class PlanetTableFrame extends SuperFrame {public PlanetTableFrame() {setTitle("TableTest");setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);TableModel model = new MyTableModel();final JTable table = new JTable(model);table.setAutoCreateRowSorter(true);// 自动排序table.setFillsViewportHeight(true);// 填充视口table.setDefaultRenderer(Color.class, new ColorRender());// 设置渲染器//table.setDefaultEditor(Color.class, new ColorTableCellEditor());// 设置编辑器table.setRowSelectionAllowed(false);add(new JScrollPane(table), BorderLayout.CENTER);JButton printButton = new JButton("Print");printButton.addActionListener(new ActionListener() {public void actionPerformed(ActionEvent event) {try {table.print();} catch (java.awt.print.PrinterException e) {e.printStackTrace();}}});JPanel buttonPanel = new JPanel();buttonPanel.add(printButton);add(buttonPanel, BorderLayout.SOUTH);}// 颜色单元格绘制器private class ColorRender extends JPanel implements TableCellRenderer {public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected,boolean hasFocus, int row, int column) {setBackground((Color) value);if (hasFocus)setBorder(UIManager.getBorder("Table.focusCellHighlightBorder"));elsesetBorder(null);return this;}}// 颜色单元格编辑器private class ColorTableCellEditor extends AbstractCellEditor implements TableCellEditor {public ColorTableCellEditor() {panel = new JPanel();chooser = new JColorChooser();dialog = JColorChooser.createDialog(null, "Planet Color", false, chooser, new ActionListener() {public void actionPerformed(ActionEvent e) {stopCellEditing();// 会调用getCellEditorValue方法的值更改模型数据}}, new ActionListener() {public void actionPerformed(ActionEvent e) {cancelCellEditing();}});dialog.addWindowListener(new WindowAdapter() {@Overridepublic void windowClosing(WindowEvent e) {cancelCellEditing();}});}// 编辑单元格时这个组件会暂时取代绘制器public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {chooser.setColor((Color) value);return panel;}@Overridepublic boolean shouldSelectCell(EventObject anEvent) {dialog.setVisible(true);return true;}@Overridepublic void cancelCellEditing() {dialog.setVisible(false);super.cancelCellEditing();}@Overridepublic boolean stopCellEditing() {dialog.setVisible(false);super.stopCellEditing();return true;}public Color getCellEditorValue() {return chooser.getColor();}@Overridepublic boolean isCellEditable(EventObject e) {// TODO 自动生成方法存根return true;}private JColorChooser chooser;private JDialog dialog;private JPanel panel;}private static final int DEFAULT_WIDTH = 400;private static final int DEFAULT_HEIGHT = 200;}class MyTableModel extends AbstractTableModel {public int getColumnCount() {return columnNames.length;}public int getRowCount() {return cells.length;}public Object getValueAt(int rowIndex, int columnIndex) {return cells[rowIndex][columnIndex];}@Overridepublic String getColumnName(int column) {// TODO 自动生成方法存根return columnNames[column];}@Override//如果不覆盖这个方法每列的类型都为Stringpublic Class<?> getColumnClass(int columnIndex) {return cells[0][columnIndex].getClass();}@Overridepublic boolean isCellEditable(int rowIndex, int columnIndex) {return true;}@Overridepublic void setValueAt(Object aValue, int rowIndex, int columnIndex) {cells[rowIndex][columnIndex] = aValue;}private Object[][] cells = { { "Mercury", 2440.0, 0, false, Color.YELLOW },{ "Venus", 6052.0, 0, false, Color.YELLOW }, { "Earth", 6378.0, 1, false, Color.BLUE },{ "Mars", 3397.0, 2, false, Color.RED }, { "Jupiter", 71492.0, 16, true, Color.ORANGE },{ "Saturn", 60268.0, 18, true, Color.ORANGE }, { "Uranus", 25559.0, 17, true, Color.BLUE },{ "Neptune", 24766.0, 8, true, Color.BLUE }, { "Pluto", 1137.0, 1, false, Color.BLACK } };private String[] columnNames = { "Planet", "Radius", "Moons", "Gaseous", "Color" };}

 可以看到布尔类型和Color类型的值都使用了绘制器