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John Wheeler · Guest

I created a custom JComboBox.KeySelectionManager that allows
progressive key selection. For instance, when installed in a combo box
populated with U.S. states, a user can type 'ar' and the combo box
will select 'Arizona' instead of 'Rhode Island.'

I install combo boxes with these KeySelectionManagers as JTable
CellEditors. When the JTable passes focus to the component, I type one
key, editing is stopped, and focus returns to the table (BTW, I have
setSurrendersFocusOnKeystroke(true)). Consequently, the
KeySelectionManager's behavior is not realized. In order to intercept
calls to editingStopped, I created a subclass of JTable with an
overridden editingStopped method that installs KeyAdapter's on the
combo boxes and when 'tab' is pressed, i call super.editingStopped
(code below). Now the combo boxes retain focus, but mouse events do
not stop editing like they used to. So, if I begin editing in a combo
box and click another cell, the editing session doesn't stop.

public void editingStopped(final ChangeEvent ce) {
final DefaultCellEditor dce = (DefaultCellEditor)
ce.getSource();
if (!(dce.getComponent() instanceof JComboBox)) {
super.editingStopped(ce);
return;
}

dce.getComponent().addKeyListener(new KeyAdapter() {
public void keyTyped(KeyEvent ke) {
if (ke.getKeyChar() == KeyEvent.VK_TAB)
TxTable.super.editingStopped(ce);
}
});
}

Can anyone help?

Kleopatra · Guest

John Wheeler wrote:

John Wheeler · Guest

thanks for your insight on the protocol. I'm looking into it now.

John Wheeler · Guest

I created a table cell editor that extends JComboBox and implements
TableCellEditor. It's constructor installs my custom key selection
manager (I followed the JScrollBar sample from Chapter 15 of Eckstein,
Loy, and Wood) . I got what I wanted, but I don't know why. my
fireEditingStopped implementation is similar to
AbstractTableCellEditor's implementation. I guess I don't understand
the protocol these components use, but I am satisfied with how things
are going. Are you aware of any ramifications I should know about?

public class AshtonComboBoxTableCellEditor extends JComboBox
implements TableCellEditor {

protected transient Vector listeners;
protected transient Object origValue;

public AshtonComboBoxTableCellEditor(Vector parts) {
setKeySelectionManager(new AshtonComboBoxKeySM());
listeners = new Vector();
for (int i=0, n=parts.size(); i<n; i++)
addItem(parts.get(i));
}

public Component getTableCellEditorComponent(JTable table, Object
value,
boolean isSelected,
int row, int column)
{
if (value == null)
return this;

setSelectedItem(value);
table.setRowSelectionInterval(row, row);
table.setColumnSelectionInterval(column, column);
origValue = getSelectedItem();

return this;
}

public Object getCellEditorValue() {
return getSelectedItem();
}

public boolean isCellEditable(EventObject anEvent) {
return true;
}

public boolean shouldSelectCell(EventObject anEvent) {
return true;
}

public boolean stopCellEditing() {
fireEditingStopped();
return true;
}

public void cancelCellEditing() {
fireEditingCancelled();
}

public void addCellEditorListener(CellEditorListener l) {
listeners.addElement(l);
}

public void removeCellEditorListener(CellEditorListener l) {
listeners.removeElement(l);
}

protected void fireEditingCancelled() {
setSelectedItem(origValue);
ChangeEvent ce = new ChangeEvent(this);
for (int i=listeners.size()-1; i>=0; i--)
((CellEditorListener)listeners.elementAt(i)).editingCanceled(ce);
}

protected void fireEditingStopped() {
ChangeEvent ce = new ChangeEvent(this);
for (int i=listeners.size()-1; i>=0; i--)
((CellEditorListener)listeners.elementAt(i)).editingStopped(ce);
}

Kleopatra · Guest

John Wheeler wrote: