@Override
 public boolean beforeClose() {
   rewardsItemStoreListPresenter.unbind();
   return true;
 }
 public void setModel(Object model) {
   this.model = model;
   rewardsItemStoreListPresenter.bind();
 }
 @Override
 public Widget asWidget() {
   return rewardsItemStoreListPresenter.getDisplay().asWidget();
 }