NullReferenceException in apps on Windows 8 RTM

I migrate an app from windows 8 RP to RTM.

I didn’t have problem on RP but on RTM SQLite throw very often an exception when my app launch.

Here is the exception details:

  System.NullReferenceException was unhandled by user code
  HResult=-2147467261
  Message=Object reference not set to an instance of an object.
  Source=mscorlib
  StackTrace:
       at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)
       at System.Collections.Generic.Dictionary`2.set_Item(TKey key, TValue value)
       at SQLite.SQLiteConnection.GetMapping(Type type) in \SQLite.cs:line 234
       at SQLite.SQLiteConnection.CreateTable(Type ty) in \SQLite.cs:line 308
       at SQLite.SQLiteAsyncConnection.<>c__DisplayClass1.<CreateTablesAsync>b__0() in \SQLiteAsync.cs:line 

94
       at System.Threading.Tasks.Task`1.InnerInvoke()
       at System.Threading.Tasks.Task.Execute()

Can you investigate on it?

[jamiepenney]

I have the same problem. It happens when I try to call CreateTableAsync like so:

var connection = new SQLiteAsyncConnection("music");
await connection.CreateTableAsync<LibraryEntry>();

And LibraryEntry is this:

    public class LibraryEntry
    {
        [PrimaryKey, AutoIncrement]
        public int Id { get; set; }

        public LibraryEntry() {}

        public LibraryEntry(string path)
        {
            Path = path;
        }

        public string Path   { get; private set; }
        public string Artist { get; set; }
        public string Album  { get; set; }
        public string Title  { get; set; }
        public uint TrackNumber { get; set; }
    }

The Create table call is in an async method that gets called on app startup. I have the same stack trace as the OP.

[stevebgit]

http://channel9.msdn.com/Events/TechEd/NorthAmerica/2013/WPH-B306#fbid=

At about 34:00, in Andy Wigley’s video above, there is what appears to be a good solution to avoiding the async race condition problem, when accessing a sqlite db ( even though he’s lecturing about SqliteRT).

The GetDatabaseAsync() function, specifically.