Question

我目前在我的视图模型中使用此方法，该方法在用户单击网格行时触发：

    public ICommand EmailPopUpCmd { get; set; }
    private void EmailPopUp(object sender) {
        //ToDo: pdf viewer pop up
        var test = sender;
        var email = new EmailView { DataContext = new MailVM() };
        email.Visibility = Visibility.Visible;
    }

我想要显示的用户控件如下所示：

<UserControl x:Class="Sybrin.UI.MailViewer.Views.EmailView"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
         xmlns:fixed="clr-namespace:Telerik.Windows.Documents.Fixed;assembly=Telerik.Windows.Controls.FixedDocumentViewers"
         xmlns:converters="clr-namespace:Telerik.Windows.Documents.Converters;assembly=Telerik.Windows.Controls.FixedDocumentViewers"
         xmlns:local="clr-namespace:Sybrin.UI.MailViewer.Helpers"
         mc:Ignorable="d"
         d:DesignHeight="300" d:DesignWidth="300"
         DataContext="{Binding}">
<Grid>
    <Grid.Resources>
        <local:BoolToDisplayConverter x:Key="BoolToDisplayConverter"/>
    </Grid.Resources>
    <Grid.RowDefinitions>
        <RowDefinition Height="auto" />
        <RowDefinition Height="0.25*" />
        <RowDefinition Height="*" />
        <RowDefinition Height="auto" />
    </Grid.RowDefinitions>
    <telerik:RadToolBar DataContext="{Binding ElementName=pdfViewer, Path=CommandDescriptors}">
        <telerik:RadToolBar.Resources>
            <converters:FixedDocumentViewerModeConverter x:Key="ModeConverter"/>
        </telerik:RadToolBar.Resources>
        <telerik:RadToggleButton IsChecked="{Binding FixedDocumentViewer.Mode, Mode=TwoWay, Converter={StaticResource ModeConverter}, ConverterParameter=Pan}"
                                 Margin="2"
                                 Padding="0"
                                 IsBackgroundVisible="False"
                                 HorizontalAlignment="Left"
                                 VerticalAlignment="Stretch"
                                 >
            <ToolTipService.ToolTip>
                <TextBlock Text="Pan" />
            </ToolTipService.ToolTip>
            <Image Source="pack://application:,,,/Telerik.Windows.Controls.FixedDocumentViewers;component/Images/hand-free.png"
                   Stretch="None" />
        </telerik:RadToggleButton>

        <telerik:RadToggleButton IsChecked="{Binding FixedDocumentViewer.Mode, Mode=TwoWay, Converter={StaticResource ModeConverter}, ConverterParameter=TextSelection}"
                                 Margin="2" Padding="0"
                                 IsBackgroundVisible="False"
                                 HorizontalAlignment="Left"
                                 VerticalAlignment="Stretch">
            <ToolTipService.ToolTip>
                <TextBlock Text="Text Selection" />
            </ToolTipService.ToolTip>
            <Image Source="pack://application:,,,/Telerik.Windows.Controls.FixedDocumentViewers;component/Images/text-selection.png"
                   Stretch="None" />
        </telerik:RadToggleButton>
    </telerik:RadToolBar>
    <telerik:RadPdfViewer x:Name="pdfEmailViewer"
                          Grid.Row="2"
                          DocumentSource="Sybrin.UI.MailViewer;Resources/TestPDF.pdf"/>
</Grid>

现在上面的方法没有显示我的用户控件。关于为什么不这样做的任何想法？

Answer 1

理想情况下，您应该在其他窗口中打开此用户控件。

创建一个新窗口并将此用户控件添加到该视图（在xaml中）。然后在按钮命令处理程序中创建该窗口的实例，只需使用窗口的Open（）方法即可完成工作。

Window myWindow = new Window（）; myWindow.Open（）;

这不是一个非常好的MVVM方式！

Answer 2

您可以将用户控件添加到要显示的xaml视图中，并将可见性绑定到属性。让值在开头折叠。当您希望控件可见时，将其更改为可见。

例如：

<Grid>
   <EmailView Visibility= "{Binding ControlVisibility}" />
</Grid>


public ICommand EmailPopUpCmd { get; set; }
private void EmailPopUp(object sender) {
    ControlVisibility = Visible;
 }

 private Visibility _controlVisibility = Collapsed;

 public Visibility ControlVisibility
 {
    get
    {
       return _controlVisibility;
    }
    set
    {
        _controlVisibility = value;
        OnPropertyChanged("ControlVisibility");
    }
 }

确保您为可见性更改实施INotifyPropertyChanged以反映在用户界面

中

显示来自另一个用户控件MVVM的用户控件

2 个答案: