WiredPrairie: Binding a table in a FlowDocument

Inspired by a post from Paul here providing a method to bind data to a FlowDocument Run object, I extended the idea to bind to a dynamic Table. I prefer the attached property syntax in Paul's approach to a "BindableRun" object that Filipe used here. I didn't change the name from Paul's code (the name was fine for my purposes).

  public static class BindableExtender

    public static Table GetBindableTable(DependencyObject obj)

      return (Table)obj.GetValue(BindableTableProperty);

    public static void SetBindableTable(DependencyObject obj, Table tbl)

      obj.SetValue(BindableTableProperty, tbl);

    public static string GetBindableText(DependencyObject obj)

      return (string)obj.GetValue(BindableTextProperty);

    public static void SetBindableText(DependencyObject obj,

        string value)

      obj.SetValue(BindableTextProperty, value);

    public static readonly DependencyProperty BindableTextProperty =

        DependencyProperty.RegisterAttached("BindableText" ,

            typeof(string) ,

                typeof(BindableExtender),

                new UIPropertyMetadata(null,

                BindableProperty_PropertyChanged));

    public static readonly DependencyProperty BindableTableProperty =

        DependencyProperty.RegisterAttached("BindableTable",

            typeof(Table),

                typeof(BindableExtender),

                new UIPropertyMetadata(null,

                BindableProperty_PropertyChanged));

    private static void BindableProperty_PropertyChanged(

        DependencyObject dependencyObject,

        DependencyPropertyChangedEventArgs e)

      if (dependencyObject is Run)

        ((Run)dependencyObject).Text = (string)e.NewValue;

      if (dependencyObject is FlowDocument)

        ((FlowDocument)dependencyObject).Blocks.Clear();

        if (e.NewValue != null)

          ((FlowDocument)dependencyObject).Blocks.Add((Block)e.NewValue);

I added all of the code that handles Tables. Not too hard to find. The important stuff regarding binding happens in the PropertyChanged event. If the object passed is a FlowDocument, the code clears the current blocks that might be in the existing FlowDocument and then adds the Table.

How did I build the table? Using code like this to build the table:

private static Table BuildTable()

  Table tbl = new Table();

  TableRowGroup rowGrp = new TableRowGroup();

  tbl.RowGroups.Add(rowGrp);

  TableRow row = new TableRow();

  rowGrp.Rows.Add(row);

  // you can style a row ...

  // row.Style = Application.Current.TryFindResource("HeaderRowStyle") as Style;

  row.Cells.Add(new TableCell(new Paragraph(new Run("DataLabel:"))));

  Paragraph pg = new Paragraph();

  // or you can style a Paragraph

  // I couldn't get pg.SetResourceReference(Paragraph.StyleProperty, "DataStyle") to work

  // it seems to never locate the Style resource properly ... the other approach below works

  // however

  // pg.Style = Application.Current.TryFindResource("DataStyle") as Style;

  pg.Inlines.Add(new Run("Some data"));

  row.Cells.Add(pg);

  return tbl;

I added a property to the class bound by the UI:

    public Table Metadata

      get { return BuildTable(); }

Then, in the XAML, I bound to the property:

<FlowDocument local:BindableExtender.BindableTable="{Binding Path=Metadata}">

  <Paragraph/>

</FlowDocument>

The important thing to note here is the use of the attached property: local:BindableExtender.BindableTable.

The local namespace refers back to the host namespace (and since it's in the same assembly, the syntax just includes the namespace):

xmlns:local="clr-namespace:PhotoScroll"

Technorati tags: C#, WPF

Binding a table in a FlowDocument

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