Display display = new Display();
Shell shell = new Shell(display);
shell.setLayout(new FillLayout());
final ComboViewer combo = new ComboViewer(shell, SWT.NONE);
	
combo.setContentProvider(new ArrayContentProvider());
combo.setLabelProvider(new LabelProvider());
combo.setInput(new String[]{"1","2","3","4"});
combo.getCombo().setText("0");

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