@Override
 protected Widget loadComponent() {
   if (algebrap == null) {
     algebrap = new ScrollPanel(); // temporarily
     algebrap.setSize("100%", "100%");
     algebrap.setAlwaysShowScrollBars(false);
   }
   if (app != null) {
     // force loading the algebra view,
     // as loadComponent should only load when needed
     setAlgebraView((AlgebraViewW) app.getAlgebraView());
     aview.setInputPanel();
   }
   return algebrap;
 }
 @Override
 public void onResize() {
   if (aview != null) {
     aview.resize();
   }
 }
 @Override
 protected Widget loadStyleBar() {
   return aview.getStyleBar(true);
 }