WPF子菜单位置

Question

我有以下菜单，我不希望子菜单项超出应用程序窗口，我希望它们显示在按下的菜单项的右侧，而不是左侧。有什么建议吗？

<Menu DockPanel.Dock="Top" x:Name="MainMenu" Height="25">
    <Menu.Background>
        <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
            <GradientStop Color="Black" Offset="0"/>
            <GradientStop Color="#FF4C5568" Offset="1"/>
        </LinearGradientBrush>
    </Menu.Background>
    <MenuItem Header="Medio" Foreground="White"  HorizontalContentAlignment="Right" HorizontalAlignment="Right">
        <MenuItem Header="Abrir archivo" VerticalAlignment="Top" HorizontalContentAlignment="Right" HorizontalAlignment="Left" x:Name="OpenVideoFile" Foreground="Black"/>
        <MenuItem Header="Abrir disco" VerticalAlignment="Top" HorizontalContentAlignment="Right" HorizontalAlignment="Left" x:Name="OpenVideoDisc" Foreground="Black"/>
    </MenuItem>
    <MenuItem Header="Reproducci?n" SubmenuOpened="MenuItem_SubmenuOpened" IsEnabled="{Binding IsReady}" Foreground="White" HorizontalAlignment="Right">
        <MenuItem Header="T?tulo" Foreground="Black" x:Name="TitleList" IsEnabled="{Binding IsDisc}" ItemsSource="{Binding TitleList}" ItemTemplate="{DynamicResource trackMenuItemTemplate}"/>
        <MenuItem Header="Cap?tulo" Foreground="Black" x:Name="ChapterList" IsEnabled="{Binding IsDisc}" ItemsSource="{Binding ChapterList}" ItemTemplate="{DynamicResource trackMenuItemTemplate}"/>
        <MenuItem Header="Subt?tulo" Foreground="Black" x:Name="SubtitleList" IsEnabled="{Binding IsDisc}" ItemsSource="{Binding SubtitlesList}" ItemTemplate="{DynamicResource trackMenuItemTemplate}"/>
        <MenuItem Header="Pista V?deo" Foreground="Black" x:Name="VideoTrack" IsEnabled="{Binding IsDisc}" ItemsSource="{Binding VideoTracks}" ItemTemplate="{DynamicResource trackMenuItemTemplate}"/>
        <MenuItem Header="Pista Audio" Foreground="Black" x:Name="AudioTrack" IsEnabled="{Binding IsDisc}" ItemsSource="{Binding AudioTracks}" ItemTemplate="{DynamicResource trackMenuItemTemplate}"/>
    </MenuItem>
    <MenuItem Style="{StaticResource MenuitemStyle}" Width="452" Height="27"     >
        <MenuItem.Header>
            <Grid Visibility="Visible" MouseLeftButtonDown="WindowMouseLeftButtonDown" Background="Transparent"/>
        </MenuItem.Header>
    </MenuItem>
    <MenuItem Width="50" Height="22" Style="{StaticResource MenuitemStyle}" RenderTransformOrigin="1.17,0.409">
        <MenuItem.Header>
            <Button Width="50" BorderThickness="0" x:Name="Close" HorizontalAlignment="Right" VerticalAlignment="Bottom" Style="{StaticResource CloseStyle}" Height="22" Click="Close_Click" Margin="0,0,-26,0"/>
        </MenuItem.Header>
    </MenuItem>
</Menu>

在这里你可以看到图片：

Answer 1

我找出导致此问题的原因。由于Windows 8.1中的Microsoft新功能，它正在发生。控制面板中有一些设置 - ＆gt;平板电脑设置。取决于你是右手还是左手，你可以控制菜单的显示位置。