public ItemPage()
{
this.InitializeComponent();
this.navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += this.NavigationHelper_LoadState;
this.navigationHelper.SaveState += this.NavigationHelper_SaveState;
}
public HubPage()
{
this.InitializeComponent();
// 仅支持方向为纵向的中心
DisplayInformation.AutoRotationPreferences = DisplayOrientations.Portrait;
this.NavigationCacheMode = NavigationCacheMode.Required;
this.navigationHelper = new NavigationHelper(this);
this.navigationHelper.LoadState += this.NavigationHelper_LoadState;
this.navigationHelper.SaveState += this.NavigationHelper_SaveState;
}