在JTable中为JComboBox的Items设置一个工具提示作为CellEditor
我想为自定义combobox中的值设置工具提示值。 基本上，我的combobox包含一个人的首字母列表 – 当它们hover在我希望它显示该人的全名时。 我的combobox基本上是JTable的单元/列，它有自己的TableCellRenderer和DefaultCellEditor。 该列表是一个JList（模型中的内部类） – iv尝试直接设置’setToolTipText’方法，但似乎不起作用。
这是代码：
* JTable中的代码：*
public void setupUserCombo(Container container){ TableColumn col = getColumnModel().getColumn(3); Set values = new LinkedHashSet(); ComboUser comboUser = new ComboUser(new User("Test User")); values.add(comboUser); col.setCellEditor(new MyComboBoxEditor((ComboUser[])values.toArray(new ComboUser[0]))); col.setCellRenderer(new MyComboBoxRenderer((ComboUser[])values.toArray(new ComboUser[0]))); repaint(); } public class MyComboBoxRenderer extends JComboBox implements TableCellRenderer { private static final long serialVersionUID = 1L; public MyComboBoxRenderer(ComboUser[] items) { super(items); repaint(); } public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) { if (value != null){ System.out.println("Setting tooltip"); ((ComboUser)value).setToolTipText("TESTING!!"); } setSelectedItem(value); return this; } } public class MyComboBoxEditor extends DefaultCellEditor { private static final long serialVersionUID = 1L; public MyComboBoxEditor(ComboUser[] items) { super(new JComboBox(items)); } } *模型中的子类：*
public class ComboUser extends JLabel{ private User user; public ComboUser(User user){ if (user != null){ this.user = user; } else { this.user = new User(""); } } @Override public String toString() { return user.getInitials(); }
如果您想在编辑combobox中使用工具提示，则必须在该combobox的自定义渲染器中使用。 以下是一个简短的例子：
// some data User[] users = new User[] { new User("Clara Zetkin", "CZ"), new User("Rosa Luxemburg", "RL"), new User("Susan Sontag", "SS"), }; // the renderer for use in the editor ListCellRenderer comboRenderer = new DefaultListCellRenderer() { @Override public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) { if (value instanceof User) { setToolTipText(((User) value).getName()); value = ((User) value).getInitials(); } else { setToolTipText(null); } return super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); } }; JComboBox editingCombo = new JComboBox(users); editingCombo.setRenderer(comboRenderer); JTable table = new JTable(3, 2); // set up the editor for the first column table.getColumnModel().getColumn(0).setCellEditor(new DefaultCellEditor(editingCombo)); // the renderer to use in the table TableCellRenderer renderer = new DefaultTableCellRenderer() { @Override protected void setValue(Object value) { if (value instanceof User) { setToolTipText(((User) value).getInitials()); value = ((User) value).getName(); } else { setToolTipText(null); } super.setValue(value); } }; table.getColumnModel().getColumn(0).setCellRenderer(renderer);
例如， 参见JTable教程 ，测试代码示例
import java.awt.BorderLayout; import javax.swing.DefaultCellEditor; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.AbstractTableModel; import javax.swing.table.DefaultTableCellRenderer; import javax.swing.table.TableCellRenderer; import javax.swing.table.TableColumn; import java.awt.Component; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.ArrayList; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JList; import javax.swing.plaf.basic.BasicComboBoxRenderer; public class TableRenderDemo extends JPanel { private static final long serialVersionUID = 1L; public TableRenderDemo() { super(new BorderLayout(5, 5)); final JTable table = new JTable(new MyTableModel()); table.setPreferredScrollableViewportSize(table.getPreferredSize()); table.setFillsViewportHeight(true); table.setRowHeight(20); JScrollPane scrollPane = new JScrollPane(table); initColumnSizes(table); setUpSportColumn(table, table.getColumnModel().getColumn(2)); add(scrollPane, BorderLayout.CENTER); JButton resetButton = new JButton("Reset to default"); resetButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { for (int i = 0; i < table.getRowCount(); i++) { table.getModel().setValueAt("None of the above", i, 2); } } }); add(resetButton, BorderLayout.SOUTH); } private void initColumnSizes(JTable table) { MyTableModel model = (MyTableModel) table.getModel(); TableColumn column = null; Component comp = null; int headerWidth = 0; int cellWidth = 0; Object[] longValues = model.longValues; TableCellRenderer headerRenderer = table.getTableHeader().getDefaultRenderer(); for (int i = 0; i < 5; i++) { column = table.getColumnModel().getColumn(i); comp = headerRenderer.getTableCellRendererComponent(null, column.getHeaderValue(), false, false, 0, 0); headerWidth = comp.getPreferredSize().width; comp = table.getDefaultRenderer(model.getColumnClass(i)).getTableCellRendererComponent(table, longValues[i], false, false, 0, i); cellWidth = comp.getPreferredSize().width; column.setPreferredWidth(Math.max(headerWidth, cellWidth)); } } private void setUpSportColumn(JTable table, TableColumn sportColumn) { ArrayList listSomeString = new ArrayList (); listSomeString.add("Snowboarding"); listSomeString.add("Rowing"); listSomeString.add("Knitting"); listSomeString.add("Speed reading"); listSomeString.add("Pool"); listSomeString.add("None of the above"); JComboBox comboBox = new JComboBox(); comboBox.addItem(new Item(1, "-")); comboBox.addItem(new Item(2, "Snowboarding")); comboBox.addItem(new Item(3, "Rowing")); comboBox.addItem(new Item(4, "Knitting")); comboBox.addItem(new Item(5, "Speed reading")); comboBox.addItem(new Item(6, "Pool")); comboBox.addItem(new Item(7, "None of the above")); comboBox.setMaximumRowCount(3); comboBox.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { JComboBox comboBox = (JComboBox) e.getSource(); Item item = (Item) comboBox.getSelectedItem(); System.out.println(item.getId() + " : " + item.getDescription()); } }); //comboBox.setRenderer(new ItemRenderer()); sportColumn.setCellEditor(new DefaultCellEditor(comboBox)); DefaultTableCellRenderer renderer = new DefaultTableCellRenderer(); renderer.setToolTipText("Click for combo box"); sportColumn.setCellRenderer(renderer); } class ItemRenderer extends BasicComboBoxRenderer { @Override public Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus) { super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); if (value != null) { Item item = (Item) value; setText(item.getDescription().toUpperCase()); } if (index == -1) { Item item = (Item) value; setText("" + item.getId()); } return this; } } class Item { private int id; private String description; public Item(int id, String description) { this.id = id; this.description = description; } public int getId() { return id; } public String getDescription() { return description; } @Override public String toString() { return description; } } class MyTableModel extends AbstractTableModel { private static final long serialVersionUID = 1L; private String[] columnNames = {"First Name", "Last Name", "Sport", "# of Years", "Vegetarian"}; private Object[][] data = {{"Kathy", "Smith", "Snowboarding", new Integer(5), false}, {"John", "Doe", "Rowing", new Integer(3), true}, {"Sue", "Black", "Knitting", new Integer(2), false}, {"Jane", "White", "Speed reading", new Integer(20), true}, {"Joe", "Brown", "Pool", new Integer(10), false}}; public final Object[] longValues = {"Jane", "Kathy", "None of the above", new Integer(20), Boolean.TRUE}; @Override public int getColumnCount() { return columnNames.length; } @Override public int getRowCount() { return data.length; } @Override public String getColumnName(int col) { return columnNames[col]; } @Override public Object getValueAt(int row, int col) { return data[row][col]; } @Override public Class getColumnClass(int c) { return getValueAt(0, c).getClass(); } @Override public boolean isCellEditable(int row, int col) { if (col < 2) { return false; } else { return true; } } @Override public void setValueAt(Object value, int row, int col) { data[row][col] = value; fireTableCellUpdated(row, col); System.out.println("New value of data: " + getValueAt(row, col)); } } private static void createAndShowGUI() { JFrame frame = new JFrame("TableRenderDemo"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); TableRenderDemo newContentPane = new TableRenderDemo(); frame.setContentPane(newContentPane); frame.pack(); frame.setVisible(true); } public static void main(String[] args) { javax.swing.SwingUtilities.invokeLater(new Runnable() { @Override public void run() { createAndShowGUI(); } }); } }