WPF绑定到Listview的ItemTemplate的可见性不起作用

时间:2018-07-14 08:16:44

标签: wpf listview mvvm visibility itemtemplate

我正在使用WPF Prism.Mvvm。 我在侧面有一个导航栏,其中包含一个绑定到Itemssource的Listview。这些项目包含图像和内容。现在,我的目标是折叠项目的内容,以便导航控件仅显示图标。

我已经定义了一个Visibility绑定,在我的Listview之外的某些图像上使用了此绑定,效果很好。但是,一旦我尝试对Listview的itemtemplate中的任何内容使用确切的绑定,就什么也没有发生。 有趣的是,如果我将“可见性”设置为“不折叠”而没有约束,那么它将再次起作用。

这是我的视图

<UserControl.Resources>
    <ResourceDictionary>
        <BooleanToVisibilityConverter x:Key="booleanToVisibilityConverter" />
    </ResourceDictionary>

[...]

<DockPanel >
    <ContentControl DockPanel.Dock="Top">
        <StackPanel>
            <Button Margin="5,5,5,5" Style="{StaticResource MyButton}" Command="{Binding ExpandMenuCommand}" Content="Menu" HorizontalAlignment="Left" Width="43.017" />
            <ListView  BorderThickness="0" VerticalContentAlignment="Top" SelectionMode="Single" ItemsSource="{Binding MenuItems}" SelectedItem="{Binding SelectedItem}" Background="Transparent">
                <ListView.ItemTemplate>
                    <DataTemplate>
                        <Grid VerticalAlignment="Center">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="*" />
                                <ColumnDefinition Width="*" />
                            </Grid.ColumnDefinitions>
                            <Image Margin="0,10,0,10" Grid.Column="0" Source="{Binding ImageSource}" />
                            <TextBlock Visibility="{Binding Visibility, Converter={StaticResource booleanToVisibilityConverter}}" VerticalAlignment="Center" Margin="10,10,10,10" Grid.Column="1" Text="{Binding Content}" Background="Transparent" FontFamily="Arial" FontWeight="Bold" />
                        </Grid>
                    </DataTemplate>
                </ListView.ItemTemplate>
            </ListView>
        </StackPanel>
    </ContentControl>
    <ContentControl DockPanel.Dock="Bottom">
        <Grid>
            <Image Visibility="{Binding Visibility, Converter={StaticResource booleanToVisibilityConverter}}" HorizontalAlignment="Center" Height="59" Margin="19,0,0,25" Width="182" Source="/ModuleA;component/Images/Logo.png" VerticalAlignment="Bottom" />
        </Grid>
    </ContentControl>
</DockPanel>

现在,如果我将Visibility="{Binding Visibility, Converter={StaticResource booleanToVisibilityConverter}}"复制到该Itemtemplate上方的任何内容(例如Listview本身或Stackpanel),则其工作方式类似于Listview下的Image。但Listview.ItemTemplate中的Textblock,Image或Grid本身不会响应我的绑定。将其设置为Visibility="Collapsed"就像我打算的那样工作。

我的视图模型:

private static bool _expanded = true;

private bool _visibility = _expanded;

public bool Visibility
{
    get { return _visibility; }
    set { SetProperty(ref _visibility, value); }
}


    private void ExpandMenu()
    {
        _expanded = !_expanded;
        Visibility = _expanded;
    }

1 个答案:

答案 0 :(得分:1)

ListView.ItemTemplate是MenuItem对象的模板。我想Visibility不是MenuItem类的属性,它属于另一个视图模型。因此,您需要从其他DataContext绑定它:

<TextBlock Visibility="{Binding DataContext.Visibility, 
                                Converter={StaticResource booleanToVisibilityConverter}, 
                                RelativeSource={RelativeSource AncestorType=ListView}}" 
           VerticalAlignment="Center" 
           Margin="10,10,10,10" Grid.Column="1" 
           Text="{Binding Content}" 
           Background="Transparent" 
           FontFamily="Arial" 
           FontWeight="Bold" />