Getting exception 'Object reference not set instance of an object' in App.xaml on line 'RootFrame.Language'

Question

Currently i am working on globalization feature in windows phone 8 app. i am getting exception ('Object reference not set instance of an object') in App.xaml in following line.

RootFrame.Language = XmlLanguage.GetLanguage(AppResources.ResourceLanguage);

in AppResources.Designer.cs the definition of ResourceLangauge i have written as following.

    /// <summary>
    ///   Looks up a localized string similar to LeftToRight.
    /// </summary>
    public static string ResourceFlowDirection
    {
        get
        {
            return ResourceManager.GetString("ResourceFlowDirection", resourceCulture);
        }
    }       


    /// <summary>
    ///   Looks up a localized string similar to en-US.
    /// </summary>
    public static string ResourceLanguage
    {
        get
        {
            return ResourceManager.GetString("ResourceLanguage", resourceCulture);
        }
    }

Please give me suggession where and what i am doing wrong ? Thank you in advance.

Answer 1

I have not written two keys in my AppResources.resx files keys are

ResourceFlowDirection   LeftToRight 
ResourceLanguage            en-US

i found this during debugging.