public MainPage()
 {
     this.InitializeComponent();
     this.navigationHelper = new NavigationHelper(this);
     this.navigationHelper.LoadState += navigationHelper_LoadState;
     this.navigationHelper.SaveState += navigationHelper_SaveState;
 }
        public MainPage()
        {
            this.InitializeComponent();
            this.navigationHelper = new NavigationHelper(this);
            this.navigationHelper.LoadState += navigationHelper_LoadState;
            this.navigationHelper.SaveState += navigationHelper_SaveState;

            enemyTimer.Tick += EnemyTimer_Tick;
            enemyTimer.Interval = TimeSpan.FromSeconds(2);

            targetTimer.Tick += TargetTimer_Tick;
            targetTimer.Interval = TimeSpan.FromSeconds(.1);
        }