Fixed #111- Added the ability to change the language within the app

ModernFlyouts/Classes/AppDataHelper.cs

@@ -259,6 +259,12 @@ public static Orientation SessionsPanelOrientation
             set => SetEnum(value);
         }
 
+        public static string Language
+        {
+            get => GetString();
+            set => SetString(value);
+        }
+
         #endregion
     }
 }

ModernFlyouts/Navigation/GeneralSettingsPage.xaml

@@ -14,6 +14,9 @@
             <GroupBox Header="{x:Static resx:Strings.Settings_Behavior}">
                 <ui:ToggleSwitch Header="{x:Static resx:Strings.Settings_RunAtStartup}" IsOn="{Binding RunAtStartup}" />
             </GroupBox>
+            <ComboBox ui:ControlHelper.Header="{x:Static resx:Strings.Settings_Language}"
+                      ItemsSource="{x:Static utils:LocalizationHelper.SupportedLanguages}"
+                      SelectedItem="{Binding Path=(utils:LocalizationHelper.CurrentLanguage)}" />
             <GroupBox Header="{x:Static resx:Strings.Settings_DefaultFlyout}">
                 <StackPanel>
                     <ui:RadioButtons x:Name="DefaultFlyoutSelector"

ModernFlyouts/Program.cs

@@ -1,4 +1,5 @@
-using System;
+using ModernFlyouts.Utilities;
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.IO.Pipes;
@@ -23,6 +24,8 @@ static void Main(string[] args)
 
                 DUIHandler.ForceFindDUIAndHide(false);
 
+                LocalizationHelper.Initialize();
+
                 var app = new App();
                 app.Run();
             }

ModernFlyouts/Properties/Strings.resx

@@ -266,8 +266,14 @@
   <data name="Settings.FlyoutTopBar" xml:space="preserve">
     <value>Flyout TopBar</value>
   </data>
+  <data name="Settings.Language" xml:space="preserve">
+    <value>Language</value>
+  </data>
+  <data name="Settings.LanguageDescription" xml:space="preserve">
+    <value>Please restart the app to change the language properly</value>
+  </data>
   <data name="Settings.MaxVerticalSessionControlsCount" xml:space="preserve">
-    <value>Maximum Number of Media Session Controls vertically</value>
+    <value>Maximum Number of Media Session Controls to show vertically</value>
   </data>
   <data name="Settings.Modules" xml:space="preserve">
     <value>Modules</value>
@@ -296,6 +302,9 @@
   <data name="Settings.ShowVolumeControlInGSMTCFlyout" xml:space="preserve">
     <value>Show Volume control in Global System Media Transport (Media) Controls flyout</value>
   </data>
+  <data name="Settings.SystemDefault" xml:space="preserve">
+    <value>System Default</value>
+  </data>
   <data name="Settings.TrayIconMode" xml:space="preserve">
     <value>Tray Icon Mode</value>
   </data>

ModernFlyouts/Utilities/LocalizationHelper.cs

@@ -1,12 +1,88 @@
 using System;
+using System.Collections.ObjectModel;
+using System.ComponentModel;
 using System.Diagnostics;
 using System.Globalization;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Threading;
 using System.Windows.Data;
 
 namespace ModernFlyouts.Utilities
 {
     public class LocalizationHelper
     {
+        private static CultureInfo systemUICulture;
+
+        #region Properties
+
+        private static LanguageInfo currentLanguage;
+
+        public static LanguageInfo CurrentLanguage
+        {
+            get { return currentLanguage; }
+            set
+            {
+                if (currentLanguage != value)
+                {
+                    currentLanguage = value;
+                    OnStaticPropertyChanged();
+                    OnCurrentLanguageChanged();
+                }
+            }
+        }
+
+        public static ObservableCollection<LanguageInfo> SupportedLanguages { get; private set; }
+
+        #endregion
+
+        public static void Initialize()
+        {
+            systemUICulture = CultureInfo.CurrentUICulture;
+            SupportedLanguages = GetAllSupportedLanguages();
+            var language = AppDataHelper.Language;
+            CurrentLanguage = SupportedLanguages.First(x => x.LanguageName == language);
+        }
+
+        private static ObservableCollection<LanguageInfo> GetAllSupportedLanguages()
+        {
+            var supportedLanguages = new ObservableCollection<LanguageInfo>();
+
+            supportedLanguages.Add(new LanguageInfo(string.Empty));
+
+            var resourceManager = Properties.Strings.ResourceManager;
+            var cultures = CultureInfo.GetCultures(CultureTypes.AllCultures);
+            foreach (var culture in cultures)
+            {
+                try
+                {
+                    if (culture.Equals(CultureInfo.InvariantCulture))
+                    {
+                        continue;
+                    }
+
+                    var resourceSet = resourceManager.GetResourceSet(culture, true, false);
+                    if (resourceSet != null)
+                    {
+                        supportedLanguages.Add(new LanguageInfo(culture));
+                    }
+                }
+                catch (CultureNotFoundException)
+                {
+
+                }
+            }
+
+            return supportedLanguages;
+        }
+
+        private static void OnCurrentLanguageChanged()
+        {
+            var uiCulture = CurrentLanguage.CultureInfo ?? systemUICulture;
+            Thread.CurrentThread.CurrentUICulture = uiCulture;
+            AppDataHelper.Language = CurrentLanguage.LanguageName;
+        }
+
         public static string GetLocalisedEnumValue(Enum value)
         {
             var resourceId = $"Enums.{value.GetType().Name}.{value}";
@@ -20,6 +96,56 @@ public static string GetLocalisedEnumValue(Enum value)
                 return value.ToString();
             }
         }
+
+        public static event PropertyChangedEventHandler StaticPropertyChanged;
+
+        private static void OnStaticPropertyChanged([CallerMemberName] string propertyName = "")
+        {
+            StaticPropertyChanged?.Invoke(null, new PropertyChangedEventArgs(propertyName));
+        }
+    }
+
+    public class LanguageInfo
+    {
+        public LanguageInfo(CultureInfo cultureInfo)
+        {
+            CultureInfo = cultureInfo;
+            Initialize();
+        }
+
+        public LanguageInfo(string cultureName)
+        {
+            if (!string.IsNullOrEmpty(cultureName))
+            {
+                CultureInfo = new CultureInfo(cultureName);
+            }
+            Initialize();
+        }
+
+        public CultureInfo CultureInfo { get; private set; }
+
+        public string DisplayName { get; private set; }
+
+        public string LanguageName { get; private set; }
+
+        private void Initialize()
+        {
+            if (CultureInfo != null)
+            {
+                DisplayName = $"{CultureInfo.NativeName} - {CultureInfo.EnglishName} [{CultureInfo.Name}]";
+                LanguageName = CultureInfo.Name;
+            }
+            else
+            {
+                DisplayName = Properties.Strings.Settings_SystemDefault;
+                LanguageName = string.Empty;
+            }
+        }
+
+        public override string ToString()
+        {
+            return DisplayName;
+        }
     }
 
     public class EnumToLocalizedStringConverter : IValueConverter