Storing Variable in When Tombstone Occurs - windows-phone-8

Question

How can i store the variables in savestate() method of TombstoneHelper class to avoid Tombstone in windows phone 8.

Answer 1

I think you can try to use PhoneApplicationService.State Property - it works like Dictionary(string, object). MSDN
To save on Deactivated event:
private void Application_Deactivated(object sender, DeactivatedEventArgs e)
{
int myObject = 5;
PhoneApplicationService.Current.State.Add("myName", myObject);
}
To restore on Activated event:
private void Application_Activated(object sender, ActivatedEventArgs e)
{
var returnedOnject = PhoneApplicationService.Current.State["myName"];
}

Answer 2

Thanks Man +1 For your comment Romasz .It is now working but there is an error when app went to the tombstone stage because PhoneApplicationService State is null when your app comes from the Tombstone Stage.So i stored that phoneState in the isolated storage in application_Deactivated and retrieve from isolated Storage in application_activated.
I made simple LoginData Class where i can store my data that i have to preserving.
[DataContract]
public class LoginData
{
[DataMember]
public string Username { get; set; }
[DataMember]
public string Password { get; set; }
[DataMember]
public int EstablishmentId { get; set; }
[DataMember]
public bool chainmanager { get; set; }
[DataMember]
public string logoimage { get; set; }
public LoginData(string username, string password, int establishmentId, bool ischainmager,string logoimage)
{
this.Username = username;
this.Password = password;
this.EstablishmentId = establishmentId;
this.chainmanager = ischainmager;
this.logoimage = logoimage;
}
}
Then make method to save the Class object in app.xml
public void save(LoginData ld)
{
PhoneApplicationService phonestate = PhoneApplicationService.Current;
phonestate.State["_lOGINcREDENTIALs_"]= ld;
var settings = IsolatedStorageSettings.ApplicationSettings;
settings["Credatials"] = phonestate.State["_lOGINcREDENTIALs_"];
}
And Method to load the Class object
public void load()
{
PhoneApplicationService phonestate = PhoneApplicationService.Current;
var settings = IsolatedStorageSettings.ApplicationSettings;
object credentials;
if (settings.TryGetValue("Credatials", out credentials))
{
phonestate.State["_lOGINcREDENTIALs_"]= credentials;
}
}
and call these methods in various event like
private void Application_Launching(object sender, LaunchingEventArgs e)
{
load();
}
private void Application_Activated(object sender, ActivatedEventArgs e)
{
load();
}
private void Application_Deactivated(object sender, DeactivatedEventArgs e)
{
save();
}
private void Application_Closing(object sender, ClosingEventArgs e)
{
save();
}