import org.eclipse.swt.*;
import org.eclipse.swt.dnd.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

/**
 * @author Thomas Singer
 */
public class TreeSnippet {
	public static void main(String[] args) {
		Display display = new Display();
		Shell shell = new Shell(display);
		shell.setLayout(new FillLayout());
		final Tree tree = new Tree(shell, SWT.BORDER | SWT.FULL_SELECTION);
		for (int i = 0; i < 4; i++) {
			TreeItem iItem = new TreeItem(tree, 0);
			iItem.setData("TreeItem (0) -" + i);
			for (int j = 0; j < 4; j++) {
				TreeItem jItem = new TreeItem(iItem, 0);
				jItem.setData("TreeItem (1) -" + j);
				for (int k = 0; k < 4; k++) {
					TreeItem kItem = new TreeItem(jItem, 0);
					kItem.setData("TreeItem (2) -" + k);
					for (int l = 0; l < 4; l++) {
						TreeItem lItem = new TreeItem(kItem, 0);
						lItem.setData("TreeItem (3) -" + l);
					}
				}
			}
		}
		final Listener listener = new Listener() {
			@Override
			public void handleEvent(Event event) {
				if (event.type == SWT.EraseItem) {
					event.detail &= ~SWT.FOREGROUND;
				}
				else if (event.type == SWT.MeasureItem) {
					final TreeItem item = (TreeItem)event.item;
					final String text = (String)item.getData();
					final Point size = event.gc.stringExtent(text);
					event.width = size.x;
					event.height = size.y;
				}
				else if (event.type == SWT.PaintItem) {
					final TreeItem item = (TreeItem)event.item;
					final String text = (String)item.getData();
					event.gc.drawString(text, event.x, event.y, true);
				}
			}
		};
		tree.addListener(SWT.EraseItem, listener);
		tree.addListener(SWT.MeasureItem, listener);
		tree.addListener(SWT.PaintItem, listener);

		final DragSource source = new DragSource(tree, DND.DROP_MOVE);
		source.setTransfer(new Transfer[]{FileTransfer.getInstance()});
		source.addDragListener(new DragSourceAdapter() {
			@Override
			public void dragStart(DragSourceEvent event) {
				event.doit = false;
			}
		});

		new Text(shell, SWT.BORDER);
		shell.setSize(400, 200);
		shell.open();
		while (!shell.isDisposed()) {
			if (!display.readAndDispatch()) {
				display.sleep();
			}
		}
		display.dispose();
	}
}