Canvas 导航正在提供System.NullReferenceException
我的应用程序上的导航已中断 这是.cs 这里是 xaml 我已经注释了很多我现在没有使用的代码，因为我正在缓慢地更改应用程序的gui，并慢慢地将其实现。。 如果这有帮助的话，我愿意分享我的资料来解决这个问题 谢谢 .cs 这是xaml文件Canvas 导航正在提供System.NullReferenceException,canvas,navigation,grid,Canvas,Navigation,Grid,我的应用程序上的导航已中断 这是.cs 这里是 xaml 我已经注释了很多我现在没有使用的代码，因为我正在缓慢地更改应用程序的gui，并慢慢地将其实现。。 如果这有帮助的话，我愿意分享我的资料来解决这个问题 谢谢 .cs 这是xaml文件 <phone:PhoneApplicationPage x:Class="WPAppStudio.View.MainNews_News" xmlns="http://schemas.microsoft.com/winfx/2006/
<phone:PhoneApplicationPage
x:Class="WPAppStudio.View.MainNews_News"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:ctl="clr-namespace:WPAppStudio.Controls"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:toolkit="clr- namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
xmlns:mytoolkit="clr-namespace:MyToolkit.Controls;assembly=MyToolkit.Extended"
xmlns:mytoolkitpaging="clr-namespace:MyToolkit.Paging;assembly=MyToolkit.Extended"
mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource CustomApplicationTextBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
DataContext="{Binding Path=MainNews_NewsViewModel, Source={StaticResource ViewModelLocator}}">
<Canvas x:Name="canvas" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="800" Background="Black" ManipulationStarted="canvas_ManipulationStarted" ManipulationDelta="canvas_ManipulationDelta" ManipulationCompleted="canvas_ManipulationCompleted">
<Canvas.Resources>
<Storyboard x:Name="moveAnimation">
<DoubleAnimation Duration="0:0:0.2" To="0" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True" />
</Storyboard>
</Canvas.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0:0:0.3">
<VisualTransition.GeneratedEasingFunction>
<QuinticEase EasingMode="EaseInOut"/>
</VisualTransition.GeneratedEasingFunction>
</VisualTransition>
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal">
<Storyboard>
<DoubleAnimation Duration="0:0:0.2" To="-420" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True"/>
</Storyboard>
</VisualState>
<VisualState x:Name="LeftMenuOpened">
<Storyboard>
<DoubleAnimation Duration="0:0:0.2" To="0" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True"/>
</Storyboard>
</VisualState>
<VisualState x:Name="RightMenuOpened">
<Storyboard>
<DoubleAnimation Duration="0:0:0.2" To="-840" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Canvas CacheMode="BitmapCache" x:Name="LayoutRoot" Width="1320" VerticalAlignment="Stretch" Background="Transparent" Canvas.Left="-420" Height="768">
<!--<Grid.ColumnDefinitions>
<ColumnDefinition Width="420"/>
<ColumnDefinition Width="480"/>
<ColumnDefinition Width="420"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>-->
<Border Width="420" CacheMode="BitmapCache" Background="#222e3e" Grid.Column="0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="{Binding ActualHeight, ElementName=canvas}"/>
<Border Width="420" Margin="900,0,0,0" CacheMode="BitmapCache" Background="#222e3e" Grid.Column="2" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="{Binding ActualHeight, ElementName=canvas}"/>
<Grid x:Name="grdCommands" Margin="420,0,0,0" CacheMode="BitmapCache" Grid.Column="1" Background="#FFCFD4E2" Height="{Binding ActualHeight, ElementName=canvas}" Width="480" >
<Grid.RowDefinitions>
<RowDefinition Height="59"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid Grid.Row="0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Background="#1b4f77">
<Image Source="/neologo_Images/Image.png" HorizontalAlignment="Stretch" Margin="-10,-51,10,-62"/>
<Button Click="OpenClose_Left" Content="" HorizontalAlignment="Left" VerticalAlignment="Top" Width="71" Height="62"/>
<Button Click="OpenClose_Right" Content="" HorizontalAlignment="Right" VerticalAlignment="Top" Width="70" Height="62" Margin="0,0,10,0"/>
</Grid>
<Border Grid.Row="1" Background="#FF31363E"/>
<phone:Pivot x:Name="PanoramaMainNews_News" Grid.Row="1" Foreground="{StaticResource CustomApplicationTextBrush}" Background="{StaticResource CustomApplicationBackgroundBrush}" SelectionChanged="panoramaMainNews_News_SelectionChanged" Loaded="PanoramaMainNews_News_Loaded" Margin="0,0,0,16">
<phone:Pivot.Title>
<ProgressBar IsIndeterminate="True" Visibility="{Binding LoadingMainNews_NewsListControlCollection, Converter={StaticResource VisibilityConverter}}" />
</phone:Pivot.Title>
<phone:PivotItem x:Name="PanoramaMainNews_News0" Margin="0,0,0,25">
<phone:PivotItem.Header>
<StackPanel Orientation="Horizontal" Margin="0,7,0,0">
<TextBlock Text="spotlight " Margin="-10,0,0,0" FontWeight="Normal" FontFamily="Segoe WP"/>
</StackPanel>
</phone:PivotItem.Header>
<Grid>
<ctl:LongListSelector x:Name="MainNews_NewsListControl"
ItemsSource="{Binding MainNews_NewsListControlCollection}"
SelectedItem="{Binding SelectedMainNews_NewsListControlCollection, Mode=TwoWay}"
PagingEnabled="False"
RefreshCommand="{Binding RefreshMainNews_NewsListControlCollection}"
>
<ctl:LongListSelector.ItemTemplate>
<DataTemplate>
<Grid Margin="30" toolkit:TiltEffect.IsTiltEnabled="True" Background="Black">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition MaxHeight="80"/>
</Grid.RowDefinitions>
<Image Source="{Binding ImageUrl, TargetNullValue={StaticResource DefaultNoImageValue}}" VerticalAlignment="Top" Stretch="UniformToFill" MaxHeight="250" Margin="20,20,20,0"/>
<TextBlock TextWrapping="Wrap" FontSize="32" Foreground="{StaticResource CustomApplicationTextBrush}"
Text="{Binding Title, Converter={StaticResource SanitizeString}}" Margin="20,0" Grid.Row="1"/>
<TextBlock TextWrapping="Wrap" FontSize="18" Foreground="{StaticResource CustomApplicationTextBrush}"
TextTrimming="WordEllipsis" Text="{Binding Summary, Converter={StaticResource SanitizeString}}" Height="75" Margin="20,0,0,20" Grid.Row="2" VerticalAlignment="Top"/>
</Grid>
</DataTemplate>
</ctl:LongListSelector.ItemTemplate>
</ctl:LongListSelector>
</Grid>
</phone:PivotItem>
</phone:Pivot>
</Grid>
<HyperlinkButton Content="HyperlinkButton" Canvas.Left="947" Canvas.Top="41"/>
</Canvas>
</Canvas>
您可能应该在问题中在此发布代码示例，以及您遇到的问题的屏幕截图。我将代码放在pastebin上，因为要查看代码太长了
<phone:PhoneApplicationPage
x:Class="WPAppStudio.View.MainNews_News"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:ctl="clr-namespace:WPAppStudio.Controls"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:toolkit="clr- namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
xmlns:mytoolkit="clr-namespace:MyToolkit.Controls;assembly=MyToolkit.Extended"
xmlns:mytoolkitpaging="clr-namespace:MyToolkit.Paging;assembly=MyToolkit.Extended"
mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource CustomApplicationTextBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
DataContext="{Binding Path=MainNews_NewsViewModel, Source={StaticResource ViewModelLocator}}">
<Canvas x:Name="canvas" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="800" Background="Black" ManipulationStarted="canvas_ManipulationStarted" ManipulationDelta="canvas_ManipulationDelta" ManipulationCompleted="canvas_ManipulationCompleted">
<Canvas.Resources>
<Storyboard x:Name="moveAnimation">
<DoubleAnimation Duration="0:0:0.2" To="0" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True" />
</Storyboard>
</Canvas.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0:0:0.3">
<VisualTransition.GeneratedEasingFunction>
<QuinticEase EasingMode="EaseInOut"/>
</VisualTransition.GeneratedEasingFunction>
</VisualTransition>
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal">
<Storyboard>
<DoubleAnimation Duration="0:0:0.2" To="-420" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True"/>
</Storyboard>
</VisualState>
<VisualState x:Name="LeftMenuOpened">
<Storyboard>
<DoubleAnimation Duration="0:0:0.2" To="0" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True"/>
</Storyboard>
</VisualState>
<VisualState x:Name="RightMenuOpened">
<Storyboard>
<DoubleAnimation Duration="0:0:0.2" To="-840" Storyboard.TargetProperty="(Canvas.Left)" Storyboard.TargetName="LayoutRoot" d:IsOptimized="True"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Canvas CacheMode="BitmapCache" x:Name="LayoutRoot" Width="1320" VerticalAlignment="Stretch" Background="Transparent" Canvas.Left="-420" Height="768">
<!--<Grid.ColumnDefinitions>
<ColumnDefinition Width="420"/>
<ColumnDefinition Width="480"/>
<ColumnDefinition Width="420"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>-->
<Border Width="420" CacheMode="BitmapCache" Background="#222e3e" Grid.Column="0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="{Binding ActualHeight, ElementName=canvas}"/>
<Border Width="420" Margin="900,0,0,0" CacheMode="BitmapCache" Background="#222e3e" Grid.Column="2" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Height="{Binding ActualHeight, ElementName=canvas}"/>
<Grid x:Name="grdCommands" Margin="420,0,0,0" CacheMode="BitmapCache" Grid.Column="1" Background="#FFCFD4E2" Height="{Binding ActualHeight, ElementName=canvas}" Width="480" >
<Grid.RowDefinitions>
<RowDefinition Height="59"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid Grid.Row="0" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Background="#1b4f77">
<Image Source="/neologo_Images/Image.png" HorizontalAlignment="Stretch" Margin="-10,-51,10,-62"/>
<Button Click="OpenClose_Left" Content="" HorizontalAlignment="Left" VerticalAlignment="Top" Width="71" Height="62"/>
<Button Click="OpenClose_Right" Content="" HorizontalAlignment="Right" VerticalAlignment="Top" Width="70" Height="62" Margin="0,0,10,0"/>
</Grid>
<Border Grid.Row="1" Background="#FF31363E"/>
<phone:Pivot x:Name="PanoramaMainNews_News" Grid.Row="1" Foreground="{StaticResource CustomApplicationTextBrush}" Background="{StaticResource CustomApplicationBackgroundBrush}" SelectionChanged="panoramaMainNews_News_SelectionChanged" Loaded="PanoramaMainNews_News_Loaded" Margin="0,0,0,16">
<phone:Pivot.Title>
<ProgressBar IsIndeterminate="True" Visibility="{Binding LoadingMainNews_NewsListControlCollection, Converter={StaticResource VisibilityConverter}}" />
</phone:Pivot.Title>
<phone:PivotItem x:Name="PanoramaMainNews_News0" Margin="0,0,0,25">
<phone:PivotItem.Header>
<StackPanel Orientation="Horizontal" Margin="0,7,0,0">
<TextBlock Text="spotlight " Margin="-10,0,0,0" FontWeight="Normal" FontFamily="Segoe WP"/>
</StackPanel>
</phone:PivotItem.Header>
<Grid>
<ctl:LongListSelector x:Name="MainNews_NewsListControl"
ItemsSource="{Binding MainNews_NewsListControlCollection}"
SelectedItem="{Binding SelectedMainNews_NewsListControlCollection, Mode=TwoWay}"
PagingEnabled="False"
RefreshCommand="{Binding RefreshMainNews_NewsListControlCollection}"
>
<ctl:LongListSelector.ItemTemplate>
<DataTemplate>
<Grid Margin="30" toolkit:TiltEffect.IsTiltEnabled="True" Background="Black">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition MaxHeight="80"/>
</Grid.RowDefinitions>
<Image Source="{Binding ImageUrl, TargetNullValue={StaticResource DefaultNoImageValue}}" VerticalAlignment="Top" Stretch="UniformToFill" MaxHeight="250" Margin="20,20,20,0"/>
<TextBlock TextWrapping="Wrap" FontSize="32" Foreground="{StaticResource CustomApplicationTextBrush}"
Text="{Binding Title, Converter={StaticResource SanitizeString}}" Margin="20,0" Grid.Row="1"/>
<TextBlock TextWrapping="Wrap" FontSize="18" Foreground="{StaticResource CustomApplicationTextBrush}"
TextTrimming="WordEllipsis" Text="{Binding Summary, Converter={StaticResource SanitizeString}}" Height="75" Margin="20,0,0,20" Grid.Row="2" VerticalAlignment="Top"/>
</Grid>
</DataTemplate>
</ctl:LongListSelector.ItemTemplate>
</ctl:LongListSelector>
</Grid>
</phone:PivotItem>
</phone:Pivot>
</Grid>
<HyperlinkButton Content="HyperlinkButton" Canvas.Left="947" Canvas.Top="41"/>
</Canvas>
</Canvas>