WPF - 设置WebBrowser无法正常工作的代码可见性

Question

我有两个元素，WebBrowser和Slider，我试图隐藏一个并显示另一个，具体取决于用户打开的文档类型，PDF或视频文件（mp4）。 但是，目前，当我打开PDF文件时，WebBrowser仍然是隐藏的。

在MainWindow.xaml中，我有

<WebBrowser x:Name="PDFView" Width="600" 
                    Height="410" Visibility="{Binding PDFVisible}">
</WebBrowser>

<FFmpegFramework:MediaElement Grid.Row="0" x:Name="MediaElement"
                    Height="400" Background="Gray"  Visibility="{Binding VideoVisible}"/>

在MainWindow.xaml.cs中，我有

else if (fileName.Contains("pdf"))
{

    MainWindowViewModel dataContext = this.DataContext as MainWindowViewModel;
    dataContext.PDFVisible = Visibility.Visible;
    dataContext.VideoVisible = Visibility.Collapsed;

    //PDFView.Navigate("file:///" + fileName);
}
else if (fileName.Contains("mp4"))
{
    MainWindowViewModel dataContext = this.DataContext as MainWindowViewModel;
    dataContext.PDFVisible = Visibility.Collapsed;
    dataContext.VideoVisible = Visibility.Visible;
}

在MainWindowModel.cs中，我有：

public Visibility PDFVisible
{
    get
    {
        return fPDFVisible;
    }
    set
    {
        this.SetProperty<Visibility>(ref fPDFVisible, value);
    }
}

public Visibility VideoVisible
{
    get
    {
        return fVideoVisible;
    }
    set
    {
        this.SetProperty<Visibility>(ref fVideoVisible, value);
    }
}

private Visibility fPDFVisible = Visibility.Collapsed;
private Visibility fVideoVisible = Visibility.Visible;

Answer 1

您在.xaml.cs文件中进行此更改，而不是为什么要创建objects来更改visibility 。 您可以通过控件名称直接更改visibility

if (fileName.Contains("pdf"))
{
    PDFView.Visibility = Visibility.Visible;
    MediaElement.Visibility = Visibility.Collapsed;
}
else if (fileName.Contains("mp4"))
{
    PDFView.Visibility = Visibility.Collapsed;
    MediaElement.Visibility = Visibility.Visible;
}

并且不要忘记在绑定中更改“Mode = TwoWay”。 它还将在ViewModel更改属性

<WebBrowser x:Name="PDFView" Width="600" 
            Height="410" Visibility="{Binding PDFVisible, Mode=TwoWay}" />

<FFmpegFramework:MediaElement Grid.Row="0" x:Name="MediaElement"
                 Height="400" Background="Gray"  Visibility="{Binding VideoVisible, Mode=TwoWay}" />