public async Task <Activity> Find(long id)
{
List <Activity> myList = await activityDbHandler.Get <Activity>();
return(myList.Find(c => (c.activityId == id)));
}
public async Task <Credentials> Find(string username, string password)
{
List <Credentials> myList = await credentials_DbHandler.Get <Credentials>();
return(myList.Find(c => (c.Username == username) && (c.Password == password)));
}