public BasePage() { InitializeComponent(); // Determine the visibility of the dark background. Visibility darkBackgroundVisibility = (Visibility)Application.Current.Resources["PhoneDarkThemeVisibility"]; // Icon dark or light if (darkBackgroundVisibility == Visibility.Visible) { BitmapImage bm = new BitmapImage(new Uri(@"/Assets/calculator.png", UriKind.RelativeOrAbsolute)); iconApp.Source = bm; } else { BitmapImage bm = new BitmapImage(new Uri(@"/Assets/calculatorBlack.png", UriKind.RelativeOrAbsolute)); iconApp.Source = bm; } if (isCreated == false) { BaseBoxList.ItemsSource = BaseList.GetCurrencyStart(); isCreated = true; } else { BaseBoxList.ItemsSource = BaseList.GetCurrency(); } }