Custom TableCellRenderer -- Won't display more than 1 line of text (SSCCE)
I wrote a simple custom table cell renderer for a subclass of JTable, the purpose of which is to enable two or more lines of text to appear in the table header. I use a comma in the header title to split the name into two or more Strings, and each String is put into a JLabel and each JLabel is put into the renderer component.
I actually have this working on a different application, but when I tried to do it for another app, I can't get it to work properly, and I've looked and looked and can't see the code difference from the app that works. The example below uses a BoxLayout. With this layout manager, the first line of text only shows up. When I tried using a BorderLayout, the two lines of the header name would over-write each other. IT seems that the header row can't expand its size, even though I try setting it explicitly to a sufficiently large size. THe header text is also not center-aligned even though I set this, which may be a clue as to what's happening.
Here's my SSCCE. Just execute the main method, and you'll see the table with the header rows as described above.
import java.awt.Component;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Vector;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingConstants;
import javax.swing.UIManager;
import javax.swing.WindowConstants;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableModel;
publicclass HeaderRendererTestimplements ActionListener{
privateint WIDTH = 800;
privateint HEIGHT = 600;
private JDialog dialog;
public HeaderRendererTest(){
JButton closeButton =new JButton("Close");
closeButton.addActionListener(this);
closeButton.setActionCommand("close");
dialog =new JDialog(new JFrame(),true);
JPanel panel =new JPanel();
RCBTable table =new RCBTable(new RCBTableModel());
JScrollPane scrollPane =new JScrollPane(table);
scrollPane.setMinimumSize(new Dimension(WIDTH, HEIGHT));
panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
panel.add(scrollPane);
JPanel buttonPanel =new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel, BoxLayout.X_AXIS));
buttonPanel.add(Box.createRigidArea(new Dimension(5,0)));
buttonPanel.add(closeButton);
buttonPanel.add(Box.createHorizontalGlue());
panel.add(Box.createRigidArea(new Dimension(0,5)));
panel.add(buttonPanel);
panel.add(Box.createRigidArea(new Dimension(0,5)));
dialog.add(panel);
dialog.setSize(WIDTH, HEIGHT);
populateFields();
dialog.setLocationRelativeTo(null);
dialog.setResizable(false);
dialog.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
dialog.addWindowListener(new WindowAdapter(){
publicvoid windowClosing(WindowEvent e){
doCancel();
}
});
dialog.setVisible(true);
}
publicvoid actionPerformed(ActionEvent e){
if (e.getActionCommand().equals("close")){
dialog.dispose();
}
}
privatevoid doCancel(){
dialog.dispose();
}
privatevoid populateFields(){
}
/*** Custom table class ***/
privateclass RCBTableextends JTable{
public RCBTable(){
super();
}
public RCBTable(TableModel model){
super(model);
setRowHeight(22);
}
public JTableHeader createDefaultTableHeader(){
returnnew JTableHeader(this.getColumnModel()){
public TableCellRenderer getDefaultRenderer(){
returnnew RCBHeaderRenderer();
}
};
}
}
/*** Custom Header Renderer class ***/
privateclass RCBHeaderRendererextends JPanelimplements TableCellRenderer{
public RCBHeaderRenderer(){
super();
}
public Component getTableCellRendererComponent(
JTable table, Object value,
boolean isSelected,boolean hasFocus,
int row,int column){
JLabel label;
this.setLayout(new BoxLayout(this,BoxLayout.Y_AXIS));
setOpaque(true);
removeAll();
this.setBorder(UIManager.getBorder("TableHeader.cellBorder"));
this.setBackground(table.getTableHeader().getBackground());
String[] result = ((String)value).split(",");
for (int i = 0; i < result.length; i++){
label =new JLabel(result[i]);
label.setBackground(table.getTableHeader().getBackground());
label.setHorizontalAlignment(SwingConstants.CENTER);
label.setFont(table.getTableHeader().getFont());
this.add(label);
}
returnthis;
}
}
/*** Custom tablemodel class ***/
privateclass RCBTableModelextends DefaultTableModel{
private Object[] object ={new String(),new String(),new Boolean(null),
new Boolean(null),new String(),new Object(),new Object()};
private String[] columnNames ={"Common Name","Expires","Write to,Clipboard?",
"Write to,File? *","File Path","Display","Remove"};
public Vector data;
publicint getRowCount(){
if (data ==null){
return 0;
}
else{
return data.size();
}
}
publicint getColumnCount(){
if (columnNames ==null)
return 0;
else{
return columnNames.length;
}
}
public String getColumnName(int col){
return columnNames[col];
}
public Class getColumnClass(int col){
return object[col].getClass();
}
public Object getValueAt (int row,int col){
Object[] array = (Object[])(data.elementAt(row));
return array[(col)];
}
publicvoid setValueAt(Object value,int row,int col){
((Vector)data.get(row)).setElementAt(value,(col));
fireTableCellUpdated(row,col);
}
public String[] getColumnNames(){
return this.columnNames;
}
publicint getNumRows(){
return data.size();
}
}
/*** Main Method ***/
publicstaticvoid main (String[] args){
new HeaderRendererTest();
}
}
