迁移到 VS2013 和 Windows Store Apps for 8.1 后，我很难解决视觉状态问题。我有一个带有 AppBar“关于”按钮的应用程序，可将用户带到关于页面。工作得很好。当视图更改为纵向时，我希望“关于”页面上的堆栈面板可以更改方向。已经为此工作了几个小时，并阅读了无数具有此代码精确副本的网站，但我的将无法正常工作。有任何想法吗？
这是 AboutPage.cs 上的 C# 代码：
private void AboutPage_SizeChanged(object sender, SizeChangedEventArgs e)
{
if (e.NewSize.Height / e.NewSize.Width >= 1)
{
VisualStateManager.GoToState(this, "Portrait", true);
}
else
{
VisualStateManager.GoToState(this, "DefaultLayout", true);
}
}
这是 AboutPage.xaml 上的 XAML：
<Page
x:Name="pageRoot"
x:Class="xxxxxxxxxxxxxxxxx.AboutPage"
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:xxxxxxxxxxxxxxxxxx"
xmlns:common="using:xxxxxxxxxxxxxxx.Common"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" SizeChanged="AboutPage_SizeChanged">
<Page.Resources>
<!-- TODO: Delete this line if the key AppName is declared in App.xaml -->
<!--<x:String x:Key="AppName">xxxxxxxxxxxxxxxxxxx</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 x:Name="pageMainGrid" Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<Grid.ChildrenTransitions>
<TransitionCollection>
<EntranceThemeTransition/>
</TransitionCollection>
</Grid.ChildrenTransitions>
<Grid.RowDefinitions>
<RowDefinition Height="140"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!-- Back button and page title -->
<Grid x:Name="pageHeaderGrid">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="120"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<StackPanel
x:Name="headerStackPanel"
Grid.ColumnSpan="3"
Background="#FF4617B4"
Orientation="Horizontal" >
<Button
x:Name="backButton"
Margin="39,59,39,0"
Command="{Binding NavigationHelper.GoBackCommand, ElementName=pageRoot}"
Style="{StaticResource NavigationBackButtonNormalStyle}"
VerticalAlignment="Top"
AutomationProperties.Name="Back"
AutomationProperties.AutomationId="BackButton"
AutomationProperties.ItemType="Navigation Button"/>
<TextBlock
x:Name="pageTitle"
Style="{StaticResource HeaderTextBlockStyle}"
Grid.Column="1"
IsHitTestVisible="false"
TextWrapping="NoWrap"
VerticalAlignment="Bottom"
Margin="0,0,30,40"
Text="{StaticResource AppName}"/>
</StackPanel>
</Grid>
<Grid
x:Name="pageContentGrid"
Grid.Row="1"
Visibility="Visible">
<Grid.RowDefinitions>
<RowDefinition Height="20*"/>
<RowDefinition Height="142*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="150*"/>
<ColumnDefinition Width="372*"/>
<ColumnDefinition Width="150*"/>
</Grid.ColumnDefinitions>
<TextBlock
Grid.Column="1"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Margin="0,0,0,0"
TextAlignment="Center"
Text="About"
FontSize="48"
FontFamily="Segoe UI"/>
<ScrollViewer
BorderThickness="0,2,0,0"
BorderBrush="DarkGray"
Grid.Row="1"
Grid.Column="1"
ScrollViewer.VerticalScrollBarVisibility="Hidden"
Margin="0">
<StackPanel
Margin="40">
<TextBlock
Text="xxxxxxxxxxxxxxxxxx"
FontSize="34" />
<TextBlock
Text="by xxxxxxxxxx"
FontSize="24"/>
<StackPanel
Orientation="Vertical"
Margin="0,25,0,0">
<TextBlock
Margin="0,6,0,0"
Padding="0,0,0,0"
Text="Website:"
FontSize="24"
VerticalAlignment="Center"/>
<HyperlinkButton
Margin="0,0,0,0"
Padding="-5,0,0,0"
FontSize="20"
NavigateUri="http://www.xxxxxxxxxxxxxx.com"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Content="www.xxxxxxxxxxxxxxxxxx.com" />
</StackPanel>
<StackPanel
x:Name="emailStack"
Orientation="Vertical"
Margin="0,25,0,0">
<TextBlock
Margin="0,4,0,0"
Padding="0,0,0,0"
Text="Support Email:"
FontSize="24"
VerticalAlignment="Center"/>
<HyperlinkButton
Margin="0,0,0,0"
Padding="-5,0,0,0"
FontSize="20"
NavigateUri="mailto:xxxxxxxxxxxxxx@gmail.com"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Content="xxxxxxxxxxxxxxxxx@gmail.com" />
</StackPanel>
<TextBlock
Margin="0,30,0,0"
Text="Feedback:"
FontSize="24"/>
<TextBlock
TextWrapping="Wrap"
Margin="0,10,0,10"
FontSize="20" >
Please take a few moments to rate and review my application.
Every little bit of encouragement and/or constructive feedback
is appreciated.
<LineBreak /><LineBreak />
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
</TextBlock>
</StackPanel>
</ScrollViewer>
<Rectangle
Grid.Row="0"
Grid.Column="0"
Grid.RowSpan="2"
HorizontalAlignment="Stretch"
Fill="DarkGray" />
<Rectangle
Grid.Row="0"
Grid.Column="2"
Grid.RowSpan="2"
HorizontalAlignment="Stretch"
Fill="DarkGray" />
</Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup>
<VisualState x:Name="DefaultLayout">
<Storyboard>
</Storyboard>
</VisualState>
<VisualState x:Name="Portrait">
<Storyboard>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetProperty="(StackPanel.Orientation)"
Storyboard.TargetName="emailStack">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Orientation>Horizontal</Orientation>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</Grid>