private void StorageList_SelectionChanged(object sender, SelectionChangedEventArgs e) { if (StorageList.SelectedIndex >= 0) { if (_unitTestPage == null) { _unitTestPage = new UnitTest(); _unitTestPage.SetUnitToTest((ITestingUnit)StorageList.SelectedItem); UnitFrame.Navigate(_unitTestPage); } else { _unitTestPage.SetUnitToTest((ITestingUnit)StorageList.SelectedItem); } } }