Question

我有一个带有两个xaml的UWP应用程序呈现这个名为 SongFix.xaml （estándarview）

<Page
        x:Class="Tablaturas.Views.SongFix"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="using:Tablaturas.Views"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:cvt="using:Tablaturas.Code"
        xmlns:ctr="using:Tablaturas.Controls"
        xmlns:data="using:Tablaturas.Model"    
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        mc:Ignorable="d">
    <Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <Pivot>
            <PivotItem>
                <PivotItem.Header>
                    <TextBlock Text="Fix Info"/>
                </PivotItem.Header>
                <Grid>
                </Grid>
            </PivotItem>
            <PivotItem>
                <PivotItem.Header>
                    <TextBlock Text="Harmonize"/>
                </PivotItem.Header>
                <Grid>
                    <ListView x:Name="LstStanzas"
                              ItemsSource="{Binding SongsViewModel.SongFixViewModel.FixStructure}"
                              ItemsPanel="{StaticResource StanzaItemTemplate}"
                              Grid.Column="2"
                              HorizontalContentAlignment="Stretch"
                              ScrollViewer.HorizontalScrollBarVisibility="Disabled">
                        <ListView.ItemContainerStyle>
                            <Style TargetType="ListViewItem">
                                <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
                            </Style>
                        </ListView.ItemContainerStyle>
                        <ListView.ItemTemplate>
                            <DataTemplate>
                                <ctr:StanzaEditorControl StanzaToEdit="{Binding }" FixStructure="{Binding ElementName=LstStanzas,Path=ItemsSource}"/>
                            </DataTemplate>
                        </ListView.ItemTemplate>
                    </ListView>
                </Grid>
            </PivotItem>
        </Pivot>
        <TextBlock Text="{Binding Warnings.Message}" Visibility="{Binding SongsViewModel.SongFixViewModel.Warnings.WarningVisible,Converter={StaticResource BoolToVis}}" Style="{StaticResource WarningMessage}" Grid.Row="1"/>
        <SplitView IsPaneOpen="{Binding SongsViewModel.SongFixViewModel.SyllabeEditorIsOpen}"
                       CompactPaneLength="0"
                       OpenPaneLength="300" PaneBackground="#FF641414" PanePlacement="Right">
            <SplitView.Pane>
                <Grid>
                    <ctr:SyllabeEditorControl SyllabeViewModel="{Binding SongsViewModel.SongFixViewModel.SyllabeEditorModel,UpdateSourceTrigger=PropertyChanged,Mode=TwoWay}"/>
                </Grid>
            </SplitView.Pane>
        </SplitView>
    </Grid>
</Page>

这个名为 SongFix.DeviceFamily-Desktop.xaml

<Page
    x:Class="Tablaturas.SongFix"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:Tablaturas"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:cvt="using:Tablaturas.Code"
    xmlns:ctr="using:Tablaturas.Controls"
    xmlns:data="using:Tablaturas.Model"    
    mc:Ignorable="d">
<Grid x:Name="GrdFixEditor" Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
    <Grid.RowDefinitions>
        <RowDefinition Height="*"/>
        <RowDefinition Height="Auto"/>
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="2*"/>
        <ColumnDefinition Width="1.5*"/>
        <ColumnDefinition Width="4*"/>
    </Grid.ColumnDefinitions>
    <Grid>
    </Grid>
    <ListView x:Name="LstStanzas"
                  ItemsSource="{Binding SongsViewModel.SongFixViewModel.FixStructure}"
                  ItemsPanel="{StaticResource StanzaItemTemplate}"
                  Grid.Column="2"
                  HorizontalContentAlignment="Stretch"
                  ScrollViewer.HorizontalScrollBarVisibility="Disabled">
        <ListView.ItemContainerStyle>
            <Style TargetType="ListViewItem">
                <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
            </Style>
        </ListView.ItemContainerStyle>
        <ListView.ItemTemplate>
            <DataTemplate>
                <ctr:StanzaEditorControl StanzaToEdit="{Binding }" FixStructure="{Binding ElementName=LstStanzas,Path=ItemsSource}"/>
            </DataTemplate>
        </ListView.ItemTemplate>
    </ListView>
</Grid>

这是我的代码隐藏

namespace Tablaturas.Views
{
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a  Frame.
    /// </summary>
    public sealed partial class SongFix : Page
    {
        public SongFix()
        {
            this.InitializeComponent();
        }
    }
}

现在我的问题是当我部署到手机时一切正常，但是当部署到我的电脑时它会抛出这个错误：

An exception of type 'System.InvalidCastException' occurred in Tablaturas.exe but was not handled in user code

Additional information: Unable to cast object of type 'Windows.UI.Xaml.Controls.Grid' to type 'Windows.UI.Xaml.Controls.ListView'.

如果我删除了 SongFix.xaml 中名为 LstStanzas 的ListView，则应用会在我的电脑上正确部署。

如果错误处于标准视图，为什么在PC部署中会出现此错误？标准视图有什么问题，如果它在我的手机上正常运行？

注意：我正在使用Visual Studio Community 2015和更新2

这个版本的VS可能是这个Bug吗？

编辑1 SongFix.g.cs文件

namespace Tablaturas.Views
{
partial class SongFix : 
    global::Windows.UI.Xaml.Controls.Page, 
    global::Windows.UI.Xaml.Markup.IComponentConnector,
    global::Windows.UI.Xaml.Markup.IComponentConnector2
{
    /// <summary>
    /// Connect()
    /// </summary>
    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Windows.UI.Xaml.Build.Tasks"," 14.0.0.0")]
    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
    public void Connect(int connectionId, object target)
    {
        switch(connectionId)
        {
        case 1:
            {
                this.LstStanzas = (global::Windows.UI.Xaml.Controls.ListView)(target);
            }
            break;
        default:
            break;
        }
        this._contentLoaded = true;
    }

    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Windows.UI.Xaml.Build.Tasks"," 14.0.0.0")]
    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]
    public global::Windows.UI.Xaml.Markup.IComponentConnector GetBindingConnector(int connectionId, object target)
    {
        global::Windows.UI.Xaml.Markup.IComponentConnector returnValue = null;
        return returnValue;
    }
}
}

Answer 1

我怀疑connectionId按照XAML中元素的顺序递增。因此，在您的第一个文件中，LstStanzas的ID为1，因为它是第一个命名的元素。在第二个XAML中，GrdFixEditor是第一个命名元素并获取id 1，因此转换错误。如果我的理论是正确的，那么删除x:Name="GrdFixEditor"（离开网格，只删除名称）应该修复错误。

无法将“Windows.UI.Xaml.Controls.Grid”类型的对象强制转换为“Windows.UI.Xaml.Controls.ListView”类型

1 个答案: