WindowsPhone/WP8/WeatherInformation/WeatherInformation/ViewModels/SettingsViewModel.cs

   1 using System;
   2 using System.ComponentModel;
   3 using System.IO.IsolatedStorage;
   4 using WeatherInformation.Resources;
   5
   6 namespace WeatherInformation.ViewModels
   7 {
   8     // TODO: IMHO INotifyPropertyChanged does not do anything useful in this class... NotifyPropertyChanged has no effect :(
   9     public class SettingsViewModel : INotifyPropertyChanged
  10     {
  11         // Settings
  12         private readonly IsolatedStorageSettings _settings;
  13
  14         // The key names of _settings
  15         private const string _languageSelectionSettingKeyName = "LanguageSelection";
  16         private const string _temperatureUnitsSelectionSettingKeyName = "TemperatureUnitsSelection";
  17         private const string _forecastDayNumbersSelectionSelectionSettingKeyName = "ForecastDayNumbersSelection";
  18         private const string _tileNotificationSwitchSettingKeyName = "TileNotificationSwitch";
  19         private const string _tileNotificationSwitchContentSettingKeyName = "TileNotificationSwitchContentSetting";
  20
  21         // The default values
  22         private const int _languageSelectionSettingDefault = 0;
  23         private const int _temperatureUnitsSelectionSettingDefault = 0;
  24         private const int _forecastDayNumbersSelectionSettingDefault = 0;
  25         // Notifications off.
  26         private const bool _tileNotificationSwitchSettingDefault = false;
  27
  28
  29         public SettingsViewModel()
  30         {
  31             // You need to add a check to DesignerProperties.IsInDesignTool to that code since accessing
  32             // IsolatedStorageSettings in Visual Studio or Expression Blend is invalid.
  33             // see: http://stackoverflow.com/questions/7294461/unable-to-determine-application-identity-of-the-caller
  34             if (!System.ComponentModel.DesignerProperties.IsInDesignTool)
  35             {
  36                 // Get the _settings for this application.
  37                 _settings = IsolatedStorageSettings.ApplicationSettings;
  38             }
  39         }
  40
  41         /// <summary>
  42         /// Property to get and set language selection Setting Key.
  43         /// </summary>
  44         public int LanguageSelectionSetting
  45         {
  46             get
  47             {
  48                 return GetValueOrDefault<int>(_languageSelectionSettingKeyName, _languageSelectionSettingDefault);
  49             }
  50             set
  51             {
  52                 if (AddOrUpdateValue(_languageSelectionSettingKeyName, value))
  53                 {
  54                     Save();
  55                 }
  56                 NotifyPropertyChanged(_languageSelectionSettingKeyName);
  57             }
  58         }
  59
  60         /// <summary>
  61         /// Property to get and set temperature units selection Setting Key.
  62         /// </summary>
  63         public int TemperaruteUnitsSelectionSetting
  64         {
  65             get
  66             {
  67                 return GetValueOrDefault<int>(_temperatureUnitsSelectionSettingKeyName, _temperatureUnitsSelectionSettingDefault);
  68             }
  69             set
  70             {
  71                 if (AddOrUpdateValue(_temperatureUnitsSelectionSettingKeyName, value))
  72                 {
  73                     Save();
  74                 }
  75                 NotifyPropertyChanged(_temperatureUnitsSelectionSettingKeyName);
  76             }
  77         }
  78
  79         /// <summary>
  80         /// Property to get and set forecast day numbers selection Setting Key.
  81         /// </summary>
  82         public int ForecastDayNumbersSelectionSetting
  83         {
  84             get
  85             {
  86                 return GetValueOrDefault<int>(_forecastDayNumbersSelectionSelectionSettingKeyName, _forecastDayNumbersSelectionSettingDefault);
  87             }
  88             set
  89             {
  90                 if (AddOrUpdateValue(_forecastDayNumbersSelectionSelectionSettingKeyName, value))
  91                 {
  92                     Save();
  93                 }
  94                 NotifyPropertyChanged(_forecastDayNumbersSelectionSelectionSettingKeyName);
  95             }
  96         }
  97
  98         /// <summary>
  99         /// Turns on/off tile notification.
 100         /// </summary>
 101         public bool TileNotificationSwitchSetting
 102         {
 103             get
 104             {
 105                 bool value = GetValueOrDefault<bool>(_tileNotificationSwitchSettingKeyName, _tileNotificationSwitchSettingDefault);
 106                 if (value)
 107                 {
 108                     TileNotificationSwitchContentSetting = AppResources.SettingsTileNotificationSwitchOn;
 109                 }
 110                 else
 111                 {
 112                     TileNotificationSwitchContentSetting = AppResources.SettingsTileNotificationSwitchOff;
 113                 }
 114                 NotifyPropertyChanged(_tileNotificationSwitchContentSettingKeyName);
 115                 return value;
 116             }
 117             set
 118             {
 119                 if (AddOrUpdateValue(_tileNotificationSwitchSettingKeyName, value))
 120                 {
 121                     Save();
 122                 }
 123                 if (value)
 124                 {
 125                     TileNotificationSwitchContentSetting = AppResources.SettingsTileNotificationSwitchOn;
 126                 }
 127                 else
 128                 {
 129                     TileNotificationSwitchContentSetting = AppResources.SettingsTileNotificationSwitchOff;
 130                 }
 131                 NotifyPropertyChanged(_tileNotificationSwitchSettingKeyName);
 132                 NotifyPropertyChanged(_tileNotificationSwitchContentSettingKeyName);
 133             }
 134         }
 135
 136         /// <summary>
 137         /// Changes content switch notification setting.
 138         /// </summary>
 139         public string TileNotificationSwitchContentSetting { get; private set; }
 140
 141
 142         /// <summary>
 143         /// Get the current value of the setting, or if it is not found, set the
 144         /// setting to the default value.
 145         /// </summary>
 146         /// <typeparam name="T"></typeparam>
 147         /// <param name="Key"></param>
 148         /// <param name="defaultValue"></param>
 149         /// <returns></returns>
 150         private T GetValueOrDefault<T>(string Key, T defaultValue)
 151         {
 152             T value;
 153
 154             // You need to add a check to DesignerProperties.IsInDesignTool to that code since accessing
 155             // IsolatedStorageSettings in Visual Studio or Expression Blend is invalid.
 156             // see: http://stackoverflow.com/questions/7294461/unable-to-determine-application-identity-of-the-caller
 157             if (System.ComponentModel.DesignerProperties.IsInDesignTool)
 158             {
 159                 return defaultValue;
 160             }
 161
 162             // If the key exists, retrieve the value.
 163             if (_settings.Contains(Key))
 164             {
 165                 value = (T)_settings[Key];
 166             }
 167             // Otherwise, use the default value.
 168             else
 169             {
 170                 value = defaultValue;
 171             }
 172             return value;
 173         }
 174
 175         /// <summary>
 176         /// Update a setting value for application. If the setting does not
 177         /// exist, then add the setting.
 178         /// </summary>
 179         /// <param name="Key"></param>
 180         /// <param name="value"></param>
 181         /// <returns></returns>
 182         private bool AddOrUpdateValue(string Key, Object value)
 183         {
 184             bool valueChanged = false;
 185
 186             // You need to add a check to DesignerProperties.IsInDesignTool to that code since accessing
 187             // IsolatedStorageSettings in Visual Studio or Expression Blend is invalid.
 188             // see: http://stackoverflow.com/questions/7294461/unable-to-determine-application-identity-of-the-caller
 189             if (System.ComponentModel.DesignerProperties.IsInDesignTool)
 190             {
 191                 return false;
 192             }
 193
 194             // If the key exists
 195             if (_settings.Contains(Key))
 196             {
 197                 // If the value has changed
 198                 if (_settings[Key] != value)
 199                 {
 200                     // Store the new value
 201                     _settings[Key] = value;
 202                     valueChanged = true;
 203                 }
 204             }
 205             // Otherwise create the key.
 206             else
 207             {
 208                 _settings.Add(Key, value);
 209                 valueChanged = true;
 210             }
 211             return valueChanged;
 212         }
 213
 214         /// <summary>
 215         /// Save the _settings.
 216         /// </summary>
 217         private void Save()
 218         {
 219             // You need to add a check to DesignerProperties.IsInDesignTool to that code since accessing
 220             // IsolatedStorageSettings in Visual Studio or Expression Blend is invalid.
 221             // see: http://stackoverflow.com/questions/7294461/unable-to-determine-application-identity-of-the-caller
 222             if (System.ComponentModel.DesignerProperties.IsInDesignTool)
 223             {
 224                 return;
 225             }
 226
 227             _settings.Save();
 228         }
 229
 230         public event PropertyChangedEventHandler PropertyChanged;
 231         private void NotifyPropertyChanged(string propertyName)
 232         {
 233             PropertyChangedEventHandler handler = PropertyChanged;
 234             if (null != handler)
 235             {
 236                 handler(this, new PropertyChangedEventArgs(propertyName));
 237             }
 238         }
 239     }
 240 }