Part 3 Complete code (Windows Store apps using C#/VB and XAML)

[ This article is for Windows 8.x and Windows Phone 8.x developers writing Windows Runtime apps. If you’re developing for Windows 10, see the latest documentation ]

This topic provides the complete code sample used in the tutorial Part 3: Navigation, layout, and views.

Important This tutorial is intended for use with Microsoft Visual Studio 2013 and Windows 8.1. Parts of it will not work correctly with Microsoft Visual Studio 2012 and Windows 8.

This topic contains these sections:

  • Technologies
  • Requirements
  • View the code (XAML)

Download location

This sample is not available for download.

Technologies

Programming languages C#, Visual Basic .NET
Programming models Windows Runtime

Requirements

Minimum supported client Windows 8.1
Minimum supported server Windows Server 2012 R2
Minimum required SDK Microsoft Visual Studio Express 2012 for Windows 8

View the code (XAML)

App.xaml

App.xaml contains only generated code.

App.xaml.cs/vb

App.xaml.cs/vb is unchanged from Part 2.

MainPage.xaml

<Page
    x:Name="pageRoot"
    x:Class="HelloWorld.MainPage"
    DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:HelloWorld"
    xmlns:common="using:HelloWorld.Common"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <Page.Resources>
        <common:BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
        <!-- TODO: Delete this line if the key AppName is declared in App.xaml -->
        <x:String x:Key="AppName">Hello, world!</x:String>
        <Style x:Key="BigGreenTextStyle" TargetType="TextBlock">
            <Setter Property="Foreground" Value="Green"/>
            <Setter Property="FontSize" Value="36"/>
            <Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}"/>
            <Setter Property="TextTrimming" Value="CharacterEllipsis"/>
            <Setter Property="TextWrapping" Value="Wrap"/>
            <Setter Property="Typography.StylisticSet20" Value="True"/>
            <Setter Property="Typography.DiscretionaryLigatures" Value="True"/>
            <Setter Property="Typography.CaseSensitiveForms" Value="True"/>
            <Setter Property="LineStackingStrategy" Value="BlockLineHeight"/>
            <Setter Property="TextLineBounds" Value="TrimToBaseline"/>
            <Setter Property="OpticalMarginAlignment" Value="TrimSideBearings"/>
        </Style>
    </Page.Resources>
    <Page.TopAppBar>
        <CommandBar>
            <AppBarButton Label="AppBarButton" Icon="Pictures" Click="PhotoPageButton_Click"/>
        </CommandBar>
    </Page.TopAppBar>

    <!--
        This grid acts as a root panel for the page that defines two rows:
        * Row 0 contains the back button and page title
        * Row 1 contains the rest of the page layout
    -->
    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
        <Grid.ChildrenTransitions>
            <TransitionCollection>
                <EntranceThemeTransition/>
            </TransitionCollection>
        </Grid.ChildrenTransitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="140"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <!-- Back button and page title -->
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="120"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <AppBarButton x:Name="backButton" Icon="Back" Height="95" Margin="10,46,10,0"
                          Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}" 
                          Visibility="{Binding IsEnabled, Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource Mode=Self}}"
                          AutomationProperties.Name="Back"
                          AutomationProperties.AutomationId="BackButton"
                          AutomationProperties.ItemType="Navigation Button"/>
            <TextBlock x:Name="pageTitle" Text="{StaticResource AppName}" Style="{StaticResource HeaderTextBlockStyle}" Grid.Column="1" 
                       IsHitTestVisible="false" TextWrapping="NoWrap" VerticalAlignment="Bottom" Margin="0,0,30,40"/>
        </Grid>

        <StackPanel Grid.Row="1" Margin="120,30,0,0">
            <TextBlock Text="What's your name?" Style="{ThemeResource BaseTextBlockStyle}"/>
            <StackPanel Orientation="Horizontal" Margin="0,20,0,20">
                <TextBox x:Name="nameInput" Width="300" HorizontalAlignment="Left" TextChanged="NameInput_TextChanged"/>
                <Button Content="Say &quot;Hello&quot;" Click="Button_Click"/>
            </StackPanel>
            <TextBlock x:Name="greetingOutput" Style="{StaticResource BigGreenTextStyle}"/>
            <!--<Button Content="Go to photo page" Click="PhotoPageButton_Click"/>-->
        </StackPanel>
    </Grid>
</Page>

MainPage.xaml.cs/vb

using HelloWorld.Common;
using System;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Navigation;

// The Basic Page item template is documented at http://go.microsoft.com/fwlink/p/?LinkID=234237

namespace HelloWorld
{
    /// <summary>
    /// A basic page that provides characteristics common to most applications.
    /// </summary>
    public sealed partial class MainPage : Page
    {

        private NavigationHelper navigationHelper;
        private ObservableDictionary defaultViewModel = new ObservableDictionary();

        /// <summary>
        /// This can be changed to a strongly typed view model.
        /// </summary>
        public ObservableDictionary DefaultViewModel
        {
            get { return this.defaultViewModel; }
        }

        /// <summary>
        /// NavigationHelper is used on each page to aid in navigation and 
        /// process lifetime management
        /// </summary>
        public NavigationHelper NavigationHelper
        {
            get { return this.navigationHelper; }
        }


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

        /// <summary>
        /// Populates the page with content passed during navigation.  Any saved state is also
        /// provided when recreating a page from a prior session.
        /// </summary>
        /// <param name="navigationParameter">The parameter value passed to
        /// <see cref="Frame.Navigate(Type, Object)"/> when this page was initially requested.
        /// </param>
        /// <param name="pageState">A dictionary of state preserved by this page during an earlier
        /// session.  This will be null the first time a page is visited.</param>
        private void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
        {
            // Restore values stored in session state.
            if (e.PageState != null && e.PageState.ContainsKey("greetingOutputText"))
            {
                greetingOutput.Text = e.PageState["greetingOutputText"].ToString();
            }


            // Restore values stored in app data.
            Windows.Storage.ApplicationDataContainer roamingSettings =
                Windows.Storage.ApplicationData.Current.RoamingSettings;
            if (roamingSettings.Values.ContainsKey("userName"))
            {
                nameInput.Text = roamingSettings.Values["userName"].ToString();
            }
        }

        /// <summary>
        /// Preserves state associated with this page in case the application is suspended or the
        /// page is discarded from the navigation cache.  Values must conform to the serialization
        /// requirements of <see cref="SuspensionManager.SessionState"/>.
        /// </summary>
        /// <param name="pageState">An empty dictionary to be populated with serializable state.</param>
        private void navigationHelper_SaveState(object sender, SaveStateEventArgs e)
        {
            e.PageState["greetingOutputText"] = greetingOutput.Text;

        }

        #region NavigationHelper registration

        /// The methods provided in this section are simply used to allow
        /// NavigationHelper to respond to the page's navigation methods.
        /// 
        /// Page specific logic should be placed in event handlers for the  
        /// <see cref="GridCS.Common.NavigationHelper.LoadState"/>
        /// and <see cref="GridCS.Common.NavigationHelper.SaveState"/>.
        /// The navigation parameter is available in the LoadState method 
        /// in addition to page state preserved during an earlier session.

        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            navigationHelper.OnNavigatedTo(e);
        }

        protected override void OnNavigatedFrom(NavigationEventArgs e)
        {
            navigationHelper.OnNavigatedFrom(e);
        }

        #endregion

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            greetingOutput.Text = "Hello, " + nameInput.Text + "!";
        }

        private void NameInput_TextChanged(object sender, TextChangedEventArgs e)
        {
            Windows.Storage.ApplicationDataContainer roamingSettings =
                Windows.Storage.ApplicationData.Current.RoamingSettings;
            roamingSettings.Values["userName"] = nameInput.Text;
        }

        private void PhotoPageButton_Click(object sender, RoutedEventArgs e)
        {
            // Add this code.
            if (this.Frame != null)
            {
                this.Frame.Navigate(typeof(PhotoPage));
            }
        }
    }
}
' The Basic Page item template is documented at http://go.microsoft.com/fwlink/p/?LinkID=234237

''' <summary>
''' A basic page that provides characteristics common to most applications.
''' </summary>
Public NotInheritable Class MainPage
    Inherits Page

    ''' <summary>
    ''' NavigationHelper is used on each page to aid in navigation and 
    ''' process lifetime management
    ''' </summary>
    Public ReadOnly Property NavigationHelper As Common.NavigationHelper
        Get
            Return Me._navigationHelper
        End Get
    End Property
    Private _navigationHelper As Common.NavigationHelper

    ''' <summary>
    ''' This can be changed to a strongly typed view model.
    ''' </summary>
    Public ReadOnly Property DefaultViewModel As Common.ObservableDictionary
        Get
            Return Me._defaultViewModel
        End Get
    End Property
    Private _defaultViewModel As New Common.ObservableDictionary()

    Public Sub New()

        InitializeComponent()
        Me._navigationHelper = New Common.NavigationHelper(Me)
        AddHandler Me._navigationHelper.LoadState, AddressOf NavigationHelper_LoadState
        AddHandler Me._navigationHelper.SaveState, AddressOf NavigationHelper_SaveState
    End Sub

    ''' <summary>
    ''' Populates the page with content passed during navigation.  Any saved state is also
    ''' provided when recreating a page from a prior session.
    ''' </summary>
    ''' <param name="sender">
    ''' The source of the event; typically <see cref="NavigationHelper"/>
    ''' </param>
    ''' <param name="e">Event data that provides both the navigation parameter passed to
    ''' <see cref="Frame.Navigate"/> when this page was initially requested and
    ''' a dictionary of state preserved by this page during an earlier
    ''' session.  The state will be null the first time a page is visited.</param>
    Private Sub NavigationHelper_LoadState(sender As Object, e As Common.LoadStateEventArgs)
        ' Restore values stored in session state.
        If e.PageState IsNot Nothing AndAlso e.PageState.ContainsKey("greetingOutputText") Then
            greetingOutput.Text = e.PageState("greetingOutputText").ToString()
        End If

        ' Restore values stored in app data.
        Dim roamingSettings =
            Windows.Storage.ApplicationData.Current.RoamingSettings

        If roamingSettings.Values.ContainsKey("userName") Then
            nameInput.Text = roamingSettings.Values("userName").ToString()
        End If
    End Sub

    ''' <summary>
    ''' Preserves state associated with this page in case the application is suspended or the
    ''' page is discarded from the navigation cache.  Values must conform to the serialization
    ''' requirements of <see cref="Common.SuspensionManager.SessionState"/>.
    ''' </summary>
    ''' <param name="sender">
    ''' The source of the event; typically <see cref="NavigationHelper"/>
    ''' </param>
    ''' <param name="e">Event data that provides a dictionary of state preserved by this page 
    ''' during an earlier session.  The state will be null the first time a page is visited.</param>
    Private Sub NavigationHelper_SaveState(sender As Object, e As Common.SaveStateEventArgs)
        e.PageState("greetingOutputText") = greetingOutput.Text
    End Sub

#Region "NavigationHelper registration"

    ''' The methods provided in this section are simply used to allow
    ''' NavigationHelper to respond to the page's navigation methods.
    ''' 
    ''' Page specific logic should be placed in event handlers for the  
    ''' <see cref="Common.NavigationHelper.LoadState"/>
    ''' and <see cref="Common.NavigationHelper.SaveState"/>.
    ''' The navigation parameter is available in the LoadState method 
    ''' in addition to page state preserved during an earlier session.

    Protected Overrides Sub OnNavigatedTo(e As NavigationEventArgs)
        _navigationHelper.OnNavigatedTo(e)
    End Sub

    Protected Overrides Sub OnNavigatedFrom(e As NavigationEventArgs)
        _navigationHelper.OnNavigatedFrom(e)
    End Sub

#End Region

    Private Sub Button_Click(sender As Object, e As RoutedEventArgs)
        greetingOutput.Text = "Hello, " & nameInput.Text & "!"
    End Sub

    Private Sub NameInput_TextChanged(sender As Object, e As TextChangedEventArgs) Handles nameInput.TextChanged
        Dim roamingSettings = Windows.Storage.ApplicationData.Current.RoamingSettings
        roamingSettings.Values("userName") = nameInput.Text
    End Sub

    Private Sub PhotoPageButton_Click(sender As Object, e As RoutedEventArgs)
        ' Add this code.
        If Me.Frame IsNot Nothing Then
            Me.Frame.Navigate(GetType(PhotoPage))
        End If
    End Sub
End Class

PhotoPage.xaml

<Page
    x:Name="pageRoot"
    x:Class="HelloWorld.PhotoPage"
    DataContext="{Binding DefaultViewModel, RelativeSource={RelativeSource Self}}"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:HelloWorld"
    xmlns:common="using:HelloWorld.Common"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d" NavigationCacheMode="Enabled"
    SizeChanged="PhotoPage_SizeChanged">

    <Page.Resources>
        <common:BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
        <!-- TODO: Delete this line if the key AppName is declared in App.xaml -->
        <x:String x:Key="AppName">Hello, photo!</x:String>
    </Page.Resources>

    <!--
        This grid acts as a root panel for the page that defines two rows:
        * Row 0 contains the back button and page title
        * Row 1 contains the rest of the page layout
    -->
    <Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
        <Grid.ChildrenTransitions>
            <TransitionCollection>
                <EntranceThemeTransition/>
            </TransitionCollection>
        </Grid.ChildrenTransitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="140"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <!-- Back button and page title -->
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="120"/>
                <ColumnDefinition Width="*"/>
            </Grid.ColumnDefinitions>
            <AppBarButton x:Name="backButton" Icon="Back" Height="95" Margin="10,46,10,0"
                          Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}" 
                          Visibility="{Binding IsEnabled, Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource Mode=Self}}"
                          AutomationProperties.Name="Back"
                          AutomationProperties.AutomationId="BackButton"
                          AutomationProperties.ItemType="Navigation Button"/>
            <TextBlock x:Name="pageTitle" Text="{StaticResource AppName}" Style="{StaticResource HeaderTextBlockStyle}" Grid.Column="1" 
                       IsHitTestVisible="false" TextWrapping="NoWrap" VerticalAlignment="Bottom" Margin="0,0,30,40"/>
        </Grid>
        <Grid x:Name="contentGrid" Grid.Row="1" Margin="120,0,0,120">
            <Grid.RowDefinitions>
                <RowDefinition Height="50"/>
                <RowDefinition Height="70"/>
                <RowDefinition/>
            </Grid.RowDefinitions>
            <Button Content="Get photo"/>
            <TextBlock Grid.Row="1" TextWrapping="Wrap" Text="TextBlock" Style="{ThemeResource SubheaderTextBlockStyle}"/>
            <StackPanel x:Name="imagePanel" Grid.Row="2" Orientation="Horizontal">
                <Border BorderBrush="Gray" BorderThickness="1" Background="Gray">
                    <Image x:Name="displayImage" Source="Assets/Logo.png"/>
                </Border>
                <StackPanel Margin="20,0,0,0">
                    <TextBlock TextWrapping="Wrap" Text="File name:" 
                               Style="{ThemeResource CaptionTextBlockStyle}"/>
                    <TextBlock TextWrapping="Wrap" Text="TextBlock" 
                               Style="{ThemeResource BodyTextBlockStyle}" Margin="10,0,0,30"/>
                    <TextBlock TextWrapping="Wrap" Text="Path:" 
                               Style="{ThemeResource CaptionTextBlockStyle}"/>
                    <TextBlock TextWrapping="Wrap" Text="TextBlock" 
                               Style="{ThemeResource BodyTextBlockStyle}" Margin="10,0,0,30"/>
                    <TextBlock TextWrapping="Wrap" Text="Date created:" 
                               Style="{ThemeResource CaptionTextBlockStyle}"/>
                    <TextBlock TextWrapping="Wrap" Text="TextBlock" 
                               Style="{ThemeResource BodyTextBlockStyle}" Margin="10,0,0,30"/>
                </StackPanel>
            </StackPanel>
        </Grid>
        <VisualStateManager.VisualStateGroups>
            <VisualStateGroup>
                <VisualState x:Name="DefaultLayout">
                    <Storyboard>
                    </Storyboard>
                </VisualState>

                <VisualState x:Name="PortraitLayout">
                    <Storyboard>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(StackPanel.Orientation)" 
                                                       Storyboard.TargetName="imagePanel">
                            <DiscreteObjectKeyFrame KeyTime="0">
                                <DiscreteObjectKeyFrame.Value>
                                    <Orientation>Vertical</Orientation>
                                </DiscreteObjectKeyFrame.Value>
                            </DiscreteObjectKeyFrame>
                        </ObjectAnimationUsingKeyFrames>
                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(FrameworkElement.Margin)" 
                                                       Storyboard.TargetName="imagePanel">
                            <DiscreteObjectKeyFrame KeyTime="0">
                                <DiscreteObjectKeyFrame.Value>
                                    <Thickness>0,0,20,0</Thickness>
                                </DiscreteObjectKeyFrame.Value>
                            </DiscreteObjectKeyFrame>
                        </ObjectAnimationUsingKeyFrames>
                    </Storyboard>
                </VisualState>
            </VisualStateGroup>
        </VisualStateManager.VisualStateGroups>
    </Grid>
</Page>

PhotoPage.xaml.cs/vb

using HelloWorld.Common;
using System;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Navigation;

// The Basic Page item template is documented at http://go.microsoft.com/fwlink/p/?LinkID=234237

namespace HelloWorld
{
    /// <summary>
    /// A basic page that provides characteristics common to most applications.
    /// </summary>
    public sealed partial class PhotoPage : Page
    {
        private NavigationHelper navigationHelper;
        private ObservableDictionary defaultViewModel = new ObservableDictionary();

        /// <summary>
        /// This can be changed to a strongly typed view model.
        /// </summary>
        public ObservableDictionary DefaultViewModel
        {
            get { return this.defaultViewModel; }
        }

        /// <summary>
        /// NavigationHelper is used on each page to aid in navigation and 
        /// process lifetime management
        /// </summary>
        public NavigationHelper NavigationHelper
        {
            get { return this.navigationHelper; }
        }

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

        /// <summary>
        /// Populates the page with content passed during navigation.  Any saved state is also
        /// provided when recreating a page from a prior session.
        /// </summary>
        /// <param name="navigationParameter">The parameter value passed to
        /// <see cref="Frame.Navigate(Type, Object)"/> when this page was initially requested.
        /// </param>
        /// <param name="pageState">A dictionary of state preserved by this page during an earlier
        /// session.  This will be null the first time a page is visited.</param>
        private void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
        {
        }

        /// <summary>
        /// Preserves state associated with this page in case the application is suspended or the
        /// page is discarded from the navigation cache.  Values must conform to the serialization
        /// requirements of <see cref="SuspensionManager.SessionState"/>.
        /// </summary>
        /// <param name="pageState">An empty dictionary to be populated with serializable state.</param>
        private void navigationHelper_SaveState(object sender, SaveStateEventArgs e)
        {
        }

        #region NavigationHelper registration

        /// The methods provided in this section are simply used to allow
        /// NavigationHelper to respond to the page's navigation methods.
        /// 
        /// Page specific logic should be placed in event handlers for the  
        /// <see cref="GridCS.Common.NavigationHelper.LoadState"/>
        /// and <see cref="GridCS.Common.NavigationHelper.SaveState"/>.
        /// The navigation parameter is available in the LoadState method 
        /// in addition to page state preserved during an earlier session.

        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            navigationHelper.OnNavigatedTo(e);
        }

        protected override void OnNavigatedFrom(NavigationEventArgs e)
        {
            navigationHelper.OnNavigatedFrom(e);
        }

        #endregion

        void PhotoPage_SizeChanged(object sender, SizeChangedEventArgs e)
        {
            if (e.NewSize.Height / e.NewSize.Width >= 1)
            {
                VisualStateManager.GoToState(this, "PortraitLayout", true);
            }
            else
            {
                VisualStateManager.GoToState(this, "DefaultLayout", true);
            }
        }
    }
}
' The Basic Page item template is documented at http://go.microsoft.com/fwlink/p/?LinkID=234237

''' <summary>
''' A basic page that provides characteristics common to most applications.
''' </summary>
Public NotInheritable Class PhotoPage
    Inherits Page

    ''' <summary>
    ''' NavigationHelper is used on each page to aid in navigation and 
    ''' process lifetime management
    ''' </summary>
    Public ReadOnly Property NavigationHelper As Common.NavigationHelper
        Get
            Return Me._navigationHelper
        End Get
    End Property
    Private _navigationHelper As Common.NavigationHelper

    ''' <summary>
    ''' This can be changed to a strongly typed view model.
    ''' </summary>
    Public ReadOnly Property DefaultViewModel As Common.ObservableDictionary
        Get
            Return Me._defaultViewModel
        End Get
    End Property
    Private _defaultViewModel As New Common.ObservableDictionary()

    Public Sub New()

        InitializeComponent()
        Me._navigationHelper = New Common.NavigationHelper(Me)
        AddHandler Me._navigationHelper.LoadState, AddressOf NavigationHelper_LoadState
        AddHandler Me._navigationHelper.SaveState, AddressOf NavigationHelper_SaveState
    End Sub

    ''' <summary>
    ''' Populates the page with content passed during navigation.  Any saved state is also
    ''' provided when recreating a page from a prior session.
    ''' </summary>
    ''' <param name="sender">
    ''' The source of the event; typically <see cref="NavigationHelper"/>
    ''' </param>
    ''' <param name="e">Event data that provides both the navigation parameter passed to
    ''' <see cref="Frame.Navigate"/> when this page was initially requested and
    ''' a dictionary of state preserved by this page during an earlier
    ''' session.  The state will be null the first time a page is visited.</param>
    Private Sub NavigationHelper_LoadState(sender As Object, e As Common.LoadStateEventArgs)

    End Sub

    ''' <summary>
    ''' Preserves state associated with this page in case the application is suspended or the
    ''' page is discarded from the navigation cache.  Values must conform to the serialization
    ''' requirements of <see cref="Common.SuspensionManager.SessionState"/>.
    ''' </summary>
    ''' <param name="sender">
    ''' The source of the event; typically <see cref="NavigationHelper"/>
    ''' </param>
    ''' <param name="e">Event data that provides a dictionary of state preserved by this page 
    ''' during an earlier session.  The state will be null the first time a page is visited.</param>
    Private Sub NavigationHelper_SaveState(sender As Object, e As Common.SaveStateEventArgs)

    End Sub

#Region "NavigationHelper registration"

    ''' The methods provided in this section are simply used to allow
    ''' NavigationHelper to respond to the page's navigation methods.
    ''' 
    ''' Page specific logic should be placed in event handlers for the  
    ''' <see cref="Common.NavigationHelper.LoadState"/>
    ''' and <see cref="Common.NavigationHelper.SaveState"/>.
    ''' The navigation parameter is available in the LoadState method 
    ''' in addition to page state preserved during an earlier session.

    Protected Overrides Sub OnNavigatedTo(e As NavigationEventArgs)
        _navigationHelper.OnNavigatedTo(e)
    End Sub

    Protected Overrides Sub OnNavigatedFrom(e As NavigationEventArgs)
        _navigationHelper.OnNavigatedFrom(e)
    End Sub

#End Region


    Private Sub PhotoPage_SizeChanged(sender As Object, e As SizeChangedEventArgs) Handles pageRoot.SizeChanged
        If e.NewSize.Height / e.NewSize.Width >= 1 Then
            VisualStateManager.GoToState(Me, "PortraitLayout", True)
        Else
            VisualStateManager.GoToState(Me, "DefaultLayout", True)
        End If
    End Sub
End Class