ContextMenu作为staticresource问题

时间:2016-02-03 09:51:25

标签: c# wpf xaml caliburn.micro

在我遇到的一个问题上,我一直在摸不着头脑,最终将其追溯到一个问题,将contextmenu作为静态资源。

我遇到的问题是,当我将contextmenu移动到一个静态资源中,并使用数据触发器根据一个对象的状态加载一个上下文菜单时,按钮命令似乎卡在了关联的datacontext上第一次加载,但另一个绑定工作正常。

我所拥有的是以下视图,其中包含使用自定义项目模板的列表视图,此项目模板为:

 <DataTemplate x:Key="appListTemplate">
    <Button cal:Message.Attach="Run" HorizontalAlignment="Stretch" VerticalAlignment="Center">
        <Button.Style>
            <Style TargetType="{x:Type Button}">
                <Setter Property="Background" Value="#BBF7F7F7"/>
                <Setter Property="Cursor" Value="Hand"/>
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="{x:Type Button}">
                            <Grid Height="50" HorizontalAlignment="Stretch" Background="{TemplateBinding Background}">

                                <Border CornerRadius="5" Height="35" Width="35" Background="SkyBlue" HorizontalAlignment="Left" VerticalAlignment="Center" Margin="10,0,0,0"/>

                                <Label Content="{Binding AppName}" ToolTip="{Binding AppStatus}" VerticalAlignment="Center" Margin="50,0,0,0" FontSize="16"/>

                                <Image Source="{Binding Icon}" ToolTip="{Binding AppIconName}" Stretch="UniformToFill" Height="20" Width="20" VerticalAlignment="Center" HorizontalAlignment="Right" Margin="0,0,15,0"/>

                                <StackPanel VerticalAlignment="Top">
                                    <Line Stroke="#FFCDCDCD" Stretch="Fill" X2="1" />
                                    <Line Stroke="#FFEAEAEA" Stretch="Fill" X2="1" />
                                </StackPanel>
                            </Grid>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
                <Style.Triggers>
                    <DataTrigger Binding="{Binding AppStatus}" Value="{x:Static enum:AppStatus.DISABLED}">
                        <Setter Property="IsEnabled" Value="False"/>
                        <Setter Property="Background" Value="Lime"/>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding AppStatus}" Value="{x:Static enum:AppStatus.NOACCESS}">
                        <Setter Property="Opacity" Value="0.5"/>
                        <Setter Property="ContextMenu" Value="{StaticResource ResourceKey=NoAccessContextMenu}" />
                    </DataTrigger>
                    <DataTrigger Binding="{Binding AppStatus}" Value="{x:Static enum:AppStatus.INSTALLED}">
                        <Setter Property="ContextMenu" Value="{StaticResource ResourceKey=InstalledContextMenu}"/>
                    </DataTrigger>
                    <DataTrigger Binding="{Binding AppStatus}" Value="{x:Static enum:AppStatus.NOTINSTALLED}">
                        <Setter Property="ContextMenu" Value="{StaticResource ResourceKey=UninstalledContextMenu}"/>
                    </DataTrigger>
                    <Trigger Property="IsMouseOver" Value="True">
                        <Setter Property="Background" Value="#FFF7F7F7"/>
                    </Trigger>
                </Style.Triggers>
            </Style>
        </Button.Style>
    </Button>
</DataTemplate>

如您所见,根据状态,加载了不同的上下文菜单。这些被定义为:

 <ContextMenu x:Key="InstalledContextMenu" StaysOpen="False">
    <MenuItem Header="{Binding AppName}" HorizontalContentAlignment="Right" FontWeight="Bold" IsEnabled="False"/>
    <Separator/>
    <MenuItem x:Name="RunApplication" Header="Run" cal:Message.Attach="Run"/>
    <MenuItem Header="Uninstall" cal:Message.Attach="Uninstall"/>
</ContextMenu>
<ContextMenu x:Key="UninstalledContextMenu" StaysOpen="False">
    <MenuItem Header="{Binding AppName}" HorizontalContentAlignment="Right" FontWeight="Bold" IsEnabled="False"/>
    <Separator/>
    <MenuItem x:Name="Install" Header="Install" cal:Message.Attach="Install"/>
</ContextMenu>
<ContextMenu x:Key="NoAccessContextMenu" StaysOpen="False">
    <MenuItem Header="{Binding AppName}" HorizontalContentAlignment="Right" FontWeight="Bold" IsEnabled="False"/>
    <Separator/>
    <MenuItem x:Name="RequestAccess" Header="Request Access" cal:Message.Attach="RequestAccess"/>
</ContextMenu>

当您右键单击列表中的第一项时,会出现问题,它会正确显示选项E.G

SHIPPING
--------
Run
Uninstall

这项工作是100%,但是当您右键单击列表中的第二项时,您将获得以下内容:

PROJECTS
--------
Run
Uninstall

正如您所看到的,appname绑定更新正常,但是当您单击卸载时,它会调用运送VM上的卸载方法,它应该在项目VM上调用卸载。对于调用Shipping VM上的方法的每个项目,这将继续发生。

我完全失去了我能做些什么,甚至为什么会这样。任何帮助都是最受欢迎的。

1 个答案:

答案 0 :(得分:0)

好的,感谢一些人的暗示,我最终追踪了这一点。 这个问题是由于上下文菜单不在可视化树中而引起的,并且微软提示&#34;修复&#34;是为了让contextmenu继承它的父级datacontext,但这只发生过一次,显然在更改datacontext时,例如更改listview中的选定项时,datacontext永远不会更新。

为了解决这个问题,我将contextmenu更改为以下内容。

<ContextMenu x:Key="InstalledContextMenu" DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}" StaysOpen="False">
    <MenuItem Header="{Binding AppName}" HorizontalContentAlignment="Right" FontWeight="Bold" IsEnabled="False"/>
    <Separator/>
    <MenuItem x:Name="RunApplication" Header="Run" cal:Action.TargetWithoutContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource AncestorType=ContextMenu}}" cal:Message.Attach="Run"/>
    <MenuItem Header="Uninstall" cal:Action.TargetWithoutContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource AncestorType=ContextMenu}}" cal:Message.Attach="Uninstall"/>
</ContextMenu>
<ContextMenu x:Key="UninstalledContextMenu" DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}" StaysOpen="False">
    <MenuItem Header="{Binding AppName}" HorizontalContentAlignment="Right" FontWeight="Bold" IsEnabled="False"/>
    <Separator/>
    <MenuItem x:Name="Install" cal:Action.TargetWithoutContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource AncestorType=ContextMenu}}"  Header="Install" cal:Message.Attach="Run"/>
</ContextMenu>
<ContextMenu x:Key="NoAccessContextMenu" DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}" StaysOpen="False">
    <MenuItem Header="{Binding AppName}" HorizontalContentAlignment="Right" FontWeight="Bold" IsEnabled="False"/>
    <Separator/>
    <MenuItem x:Name="RequestAccess" cal:Action.TargetWithoutContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource AncestorType=ContextMenu}}" Header="Request Access" cal:Message.Attach="RequestAccess"/>
</ContextMenu>

如您所见,我现在为datacontext创建自己的绑定,然后在每个菜单项上为我的校准微动作设置目标上下文。对于每个菜单项,这都需要做一些屁股,但似乎是最简单的修复。