原程序：Snippet114
1，Tree支持 SWT.CHECK 类型的树。
2，单击复选框或Item产生SWT.Selection事件，如果单击的是复选框，event.detail = SWT.CHECK。
3，双击Item产生SWT.DefaultSelection
public class Snippet114 {
public static void main (String [] args) {
Display display = new Display ();
Shell shell = new Shell (display);
shell.setLayout(new FillLayout());
Tree tree = new Tree (shell, SWT.CHECK | SWT.BORDER);
for (int i=0; i<12; i++) {
TreeItem item = new TreeItem (tree, SWT.NONE);
item.setText ("Item " + i);
}
tree.addListener(SWT.Selection, new Listener() {
public void handleEvent(Event event) {
String string = event.detail == SWT.CHECK ? "Checked" : "Selected";
System.out.println (event.item + " " + string);
}
});
tree.addListener(SWT.DefaultSelection, new Listener() {
public void handleEvent(Event event) {
System.out.println ("DefaultSelection");
}
});
shell.setSize (200, 200);
shell.open ();
while (!shell.isDisposed()) {
if (!display.readAndDispatch ()) display.sleep ();
}
display.dispose ();
}
}