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Unable to launch my app on ios simulator with xamarin studio


I have a problem when I try to launch my app on ios simulator.

The build works perfectly but when I launch it, it crash at the start in the app delegate on "LoadApplication(new App());"

And i get the error : "object reference not set to an instance of an object"

Any idea what does it mean ?

In the upper left select box i chose "Debug | iPhoneSimulator" and it make my PCL solution greyish and says that the project is not built in active configuration ... is this the problem ? and if it is how do i start my app on iPhoneSimulator ?

Is it possible that i have a problem with the localization ?

this is my Localize file in iOS :

    namespace ****.iOS {
        public class Localize : ****.ILocalize {
            public System.Globalization.CultureInfo GetCurrentCultureInfo () {
                var netLanguage = "en";
            if (NSLocale.PreferredLanguages.Length > 0) {
                var pref = NSLocale.PreferredLanguages [0];
                netLanguage = pref.Replace ("_", "-");
            return new System.Globalization.CultureInfo(netLanguage);

Thank you for your help !


  • rzee7rzee7 INUniversity ✭✭✭✭✭

    Hi @Grimuldan

    It would be good, if you post stack trace here. It seems like there is an instance of a class, variable , image etc are initializing null.


  • GrimuldanGrimuldan BEMember

    This crash right at the beggining on "LoadApplication(new App());"
    To make it work i have to put XS on Debug | iPhoneSimulator mode and so my PCL Solution is "ignored" (in grey and says "Project not built in active Configuration")

    This made me unable to put breakpoint and to see modification inside my PCL i just had to clean each solution and build them one by one :/

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