如何在WPF中向FlowDocument添加页脚?

时间:2013-06-06 06:50:23

标签: c# wpf flowdocument

我的应用程序中有一个FlowDocument,如下所示:

   <FlowDocumentScrollViewer Grid.Row="1">
        <FlowDocument>
              <Section>
                    <Paragraph>Header</Paragraph>
               </Section>

               <Section>
                  <Paragraph >
                        Footer
                   </Paragraph>
               </Section>
        </FlowDocument>
   </FlowDocumentScrollViewer>

我想要的是将第一个<Section>设置为文档的顶部作为页眉,第二个作为页脚保留在文档的底部。

有人能告诉我最好的方法吗?

2 个答案:

答案 0 :(得分:2)

起点是显示how to wrap a DocumentPaginator and add decoration to the pages的博客文章。限制是它旨在直接用于打印API。它不能直接与查看者一起使用,因为它们要求文档为FlowDocument,并且无法覆盖子类中的DocumentPaginator

我为FlowDocumentPageViewer找到的解决方案有几个部分。我没有尝试将其改编为FlowDocumentScrollViewer,但可能使用相同的原则。

自定义XAML模板

我首先使用Blend提取FlowDocumentPageViewer的默认XAML模板。我实际上想要删除一些位,但页眉/页脚的关键更改是(作为统一差异)

-    <Style TargetType="{x:Type FlowDocumentPageViewer}">
+    <Style TargetType="{x:Type local:CustomFlowDocumentPageViewer}">
                         <Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" Uid="Border_47" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
                             <AdornerDecorator ClipToBounds="True" Uid="AdornerDecorator_1">
-                                <DocumentPageView DocumentPaginator="{x:Null}" KeyboardNavigation.IsTabStop="False" DocumentViewerBase.IsMasterPage="True" PageNumber="0" KeyboardNavigation.TabIndex="1" KeyboardNavigation.TabNavigation="Local" Uid="DocumentPageView_1"/>
+                                <DocumentPageView DocumentPaginator="{x:Null}" KeyboardNavigation.IsTabStop="False" DocumentViewerBase.IsMasterPage="True" PageNumber="0" KeyboardNavigation.TabIndex="1" KeyboardNavigation.TabNavigation="Local" Uid="DocumentPageView_1" x:Name="DocumentPageView_1"/>
                             </AdornerDecorator>
                         </Border>

查看器的子类

由于你应该能够从XAML diff中解决问题,我的子类称为CustomFlowDocumentPageViewer。由于FlowDocumentPageViewer要求其DocumentFlowDocument,因此尝试更改文档毫无意义。但我能做的就是拦截它并将其DocumentPaginator包装在一个自定义的中,我将其注入DocumentPageView。 XAML差异的后半部分是为了让我找到它。

        private DocumentPageView _PageView;

        public DocumentPaginator CustomDocumentPaginator { get; private set; }

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

            _PageView = (DocumentPageView)GetTemplateChild("DocumentPageView_1");
            if (_PageView != null) _PageView.DocumentPaginator = CustomDocumentPaginator;
        }

        protected override void OnDocumentChanged()
        {
            base.OnDocumentChanged();

            var doc = Document as FlowDocument;
            CustomDocumentPaginator = doc == null ? null : new DocumentPaginatorWrapper((doc as IDocumentPaginatorSource).DocumentPaginator, new Thickness { Bottom = 32 /* 0.333in */ });
            if (_PageView != null) _PageView.DocumentPaginator = CustomDocumentPaginator;
        }

当然,只有更改DocumentPageView.DocumentPaginator才会出现一个大问题:如果您调用myCustomFlowDocumentPageViewer.Print(),则会打印原始文档,而不会显示页眉和页脚。解决方案很简单但很长(约100行);如果您使用referencesource.microsoft.com,您应该能够找出如何覆盖OnPrintCommand以将CustomDocumentPaginator发送到XpsDocumentWriter而不是((IDocumentPaginatorSource)document).DocumentPaginator

包装文档分页器

我说起点是一篇博客文章,展示了如何包装DocumentPaginator。它没有提到一些细微之处,可能是因为它打算用于打印文档一次,因此作者没有碰到它们。

  1. DocumentPage是一次性的。当您从包装的分页器中获取页面时,您有责任处理它。如果不这样做,您可能会发现,当您将包装好的网页ArgumentException: Specified Visual is already a child of another Visual or the root of a CompositionTarget添加到Visual时,您可以随意导航ContainerVisual
  2. 获取ArgumentException的另一种方法是在已经有页面的包装副本时尝试包装页面。例如。如果您打印,则会发生这种情况,因为XpsDocumentWriter将请求当前正在呈现的页面副本。
  3. 因此,您需要仔细管理页面的生命周期。我的paginator包装器的修改版本是

        class DocumentPaginatorWrapper : DocumentPaginator
        {
            private Thickness _Margin;
            private DocumentPaginator _Paginator;
    
            // Required to avoid "ArgumentException: Specified Visual is already a child of another Visual or the root of a CompositionTarget" when printing
            private IDictionary<int, DocumentPage> _PageCache = new Dictionary<int, DocumentPage>();
    
            public DocumentPaginatorWrapper(DocumentPaginator paginator, Thickness margin)
            {
                _Margin = margin;
                _Paginator = paginator;
                this.PageSize = paginator.PageSize;
    
                // Events
                paginator.ComputePageCountCompleted += (s, ev) => this.OnComputePageCountCompleted(ev);
                paginator.GetPageCompleted += (s, ev) => this.OnGetPageCompleted(ev);
                paginator.PagesChanged += (s, ev) => this.OnPagesChanged(ev);
            }
    
            public override DocumentPage GetPage(int pageNumber)
            {
                DocumentPage cachedPage;
                if (_PageCache.TryGetValue(pageNumber, out cachedPage) && cachedPage.Visual != null) return cachedPage;
    
                DocumentPage page = _Paginator.GetPage(pageNumber);
    
                // Create a wrapper visual for transformation and add extras
                ContainerVisual newpage = new ContainerVisual();
    
                // TODO Transform the wrapped page, add your headers and footers.
                // This is highly idiosyncratic.
                ...
    
                // NB We assume that page.BleedBox has X=0, Y=0, Size=page.PageSize
                cachedPage = new DocumentPageWrapper(page, newpage, PageSize, new Rect(PageSize), new Rect(page.ContentBox.X, page.ContentBox.Y, page.ContentBox.Width + _Margin.Left + _Margin.Right, page.ContentBox.Height + _Margin.Top + _Margin.Bottom));
                _PageCache[pageNumber] = cachedPage;
                return cachedPage;
            }
    
            public override bool IsPageCountValid { get { return _Paginator.IsPageCountValid; } }
    
            public override int PageCount { get { return _Paginator.PageCount; } }
    
            public override Size PageSize
            {
                get { var value = _Paginator.PageSize; return new Size(value.Width + _Margin.Left + _Margin.Right, value.Height + _Margin.Top + _Margin.Bottom); }
                set { _Paginator.PageSize = new Size(value.Width - _Margin.Left - _Margin.Right, value.Height - _Margin.Top - _Margin.Bottom); }
            }
    
            public override IDocumentPaginatorSource Source { get { return _Paginator.Source; } }
        }
    
        /// <summary>
        /// It's necessary to dispose the page returned by the wrapped DocumentPaginator when the page we return is disposed,
        /// because otherwise we inconsistently get ArgumentExceptions due to the page.Visual still being in use.
        /// </summary>
        class DocumentPageWrapper : DocumentPage
        {
            internal DocumentPageWrapper(DocumentPage originalPage, Visual visual, Size pageSize, Rect bleedBox, Rect contentBox)
                : base(visual, pageSize, bleedBox, contentBox)
            {
                _OriginalPage = originalPage;
            }
    
            private DocumentPage _OriginalPage;
    
            public override void Dispose()
            {
                base.Dispose();
    
                if (_OriginalPage != null)
                {
                    _OriginalPage.Dispose();
                    _OriginalPage = null;
                }
            }
        }
    

答案 1 :(得分:0)

你可以尝试这个..希望这会有所帮助..

<Section Name="MainBody" SectionExtensions.ResetPageNumbers="True">
    <!-- Add the document title to the header -->
    <SectionExtensions.HeaderTemplate>
        <DataTemplate>
            <Border BorderBrush="Black" BorderThickness="0,0,0,1">
                <TextBlock Text="Document title" FontSize="16" />
            </Border>
        </DataTemplate>
    </SectionExtensions.HeaderTemplate>


    <!-- Add the page count to the footer -->
    <SectionExtensions.FooterTemplate>
        <DataTemplate>
            <Border BorderBrush="Black" BorderThickness="0,1,0,0">
                <TextBlock Text="{Binding}" FontSize="16" />
            </Border>
        </DataTemplate>
    </SectionExtensions.FooterTemplate>
    <Paragraph>
    ...
    </Paragraph>
</Section>