Build a tree and populate it with custom renderers and editors
/*
Java Swing, 2nd Edition
By Marc Loy, Robert Eckstein, Dave Wood, James Elliott, Brian Cole
ISBN: 0-596-00408-7
Publisher: O'Reilly
*/
// EmailTree.java
//A Simple test to see how we can build a tree and populate it. This
//application also uses custom renderers and editors.
//
public static void main(String args[]) {
EmailTree tt = new EmailTree();
tt.init();
tt.setVisible(true);
}
}
//EmailTreeCellEditor.java
//An editor that actually manages two separate editors: one for folders
//(nodes) that uses a combobox; and one for files (leaves) that uses a
//textfield.
//
class EmailTreeCellEditor implements TreeCellEditor {
public Object getCellEditorValue() { return currentEditor.getCellEditorValue();
}
// All cells are editable in this example... public boolean isCellEditable(EventObject event) { return true;
}
public boolean shouldSelectCell(EventObject event) { return currentEditor.shouldSelectCell(event);
}
public boolean stopCellEditing() { return currentEditor.stopCellEditing();
}
public void cancelCellEditing() {
currentEditor.cancelCellEditing();
}
public void addCellEditorListener(CellEditorListener l) {
nodeEditor.addCellEditorListener(l);
leafEditor.addCellEditorListener(l);
}
public void removeCellEditorListener(CellEditorListener l) {
nodeEditor.removeCellEditorListener(l);
leafEditor.removeCellEditorListener(l);
}
}
//EditorComboBox.java
//A CellEditor JComboBox subclass for use with Trees (and possibly tables).
//This version will work with any list of values passed as an Object[].
//
class EditorComboBox extends JComboBox implements CellEditor {
String value;
Vector listeners = new Vector();
// Mimic all the constructors people expect with ComboBoxes. public EditorComboBox(Object[] list) { super(list);
setEditable(false);
value = list[0].toString();
// Listen to our own action events so that we know when to stop editing.
addActionListener(new ActionListener() { public void actionPerformed(ActionEvent ae) { if (stopCellEditing()) {
fireEditingStopped();
}
}
});
}
// Implement the CellEditor methods. public void cancelCellEditing() {
}
// Stop editing only if the user entered a valid value. public boolean stopCellEditing() { try {
value = (String) getSelectedItem(); if (value == null) {
value = (String) getItemAt(0);
} return true;
} catch (Exception e) {
// Something went wrong. return false;
}
}
public Object getCellEditorValue() { return value;
}
// Start editing when the right mouse button is clicked. public boolean isCellEditable(EventObject eo) { if ((eo == null)
|| ((eo instanceof MouseEvent) && (((MouseEvent) eo)
.isMetaDown()))) { return true;
} return false;
}
public boolean shouldSelectCell(EventObject eo) { return true;
}
// Add support for listeners. public void addCellEditorListener(CellEditorListener cel) {
listeners.addElement(cel);
}
public void removeCellEditorListener(CellEditorListener cel) {
listeners.removeElement(cel);
}
protected void fireEditingStopped() { if (listeners.size() > 0) {
ChangeEvent ce = new ChangeEvent(this); for (int i = listeners.size() - 1; i >= 0; i--) {
((CellEditorListener) listeners.elementAt(i))
.editingStopped(ce);
}
}
}
}
//EmailEditor.java
//An extension of JTextField that requires an "@" somewhere in the field.
//Meant to be used as a cell editor within a JTable or JTree.
//
class EmailEditor extends JTextField implements CellEditor {
String value = "";
Vector listeners = new Vector();
// Mimic all the constructors people expect with text fields. public EmailEditor() { this("", 5);
}
public EmailEditor(String s) { this(s, 5);
}
public EmailEditor(int w) { this("", w);
}
public EmailEditor(String s, int w) { super(s, w);
// Listen to our own action events so that we know when to stop editing.
addActionListener(new ActionListener() { public void actionPerformed(ActionEvent ae) { if (stopCellEditing()) {
fireEditingStopped();
}
}
});
}
// Implement the CellEditor methods. public void cancelCellEditing() {
setText("");
}
// Stop editing only if the user entered a valid value. public boolean stopCellEditing() { try {
String tmp = getText(); int at = tmp.indexOf("@"); if (at != -1) {
value = tmp; return true;
} return false;
} catch (Exception e) {
// Something went wrong (most likely we don't have a valid integer). return false;
}
}
public Object getCellEditorValue() { return value;
}
// Start editing when the right mouse button is clicked. public boolean isCellEditable(EventObject eo) { if ((eo == null)
|| ((eo instanceof MouseEvent) && (((MouseEvent) eo)
.isMetaDown()))) { return true;
} return false;
}
public boolean shouldSelectCell(EventObject eo) { return true;
}
// Add support for listeners. public void addCellEditorListener(CellEditorListener cel) {
listeners.addElement(cel);
}
public void removeCellEditorListener(CellEditorListener cel) {
listeners.removeElement(cel);
}
protected void fireEditingStopped() { if (listeners.size() > 0) {
ChangeEvent ce = new ChangeEvent(this); for (int i = listeners.size() - 1; i >= 0; i--) {
((CellEditorListener) listeners.elementAt(i))
.editingStopped(ce);
}
}
}
}
