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

/**
 * @author Thomas Singer
 */
public class ScrollTest {

	public static void main(String[] args) {
		final Display display = new Display();

		final Shell shell = new Shell(display);
		shell.setLayout(new FillLayout());

		final Composite composite = new Composite(shell, SWT.DOUBLE_BUFFERED | SWT.V_SCROLL);
		final ScrollBar verticalBar = composite.getVerticalBar();
		verticalBar.setValues(420, 0, 1002, 24, 1, 24);

		composite.addListener(SWT.Paint, event -> {
			int selection = verticalBar.getSelection();
			final Rectangle bounds = composite.getBounds();
			final int rowHeight = event.gc.getFontMetrics().getHeight();
			while (bounds.height > 0) {
				event.gc.drawString(Integer.toString(selection++), bounds.x, bounds.y);
				bounds.y += rowHeight;
				bounds.height -= rowHeight;
			}
		});

		verticalBar.addListener(SWT.Selection, event -> composite.redraw());

		final Table table = new Table(shell, SWT.BORDER | SWT.V_SCROLL | SWT.VIRTUAL);
		table.addListener(SWT.SetData, event -> ((Item)event.item).setText("Row " + event.index));
		table.setItemCount(1002);
		table.setSelection(420);

		shell.setSize(500, 400);
		shell.open();

		while (!shell.isDisposed()) {
			if (!display.readAndDispatch()) {
				display.sleep();
			}
		}

		display.dispose();
	}
}