How can I hide a Paragraph in a FlowDocument?

Question

Is there any way to use databinding to show or hide a Paragraph within a FlowDocument? (I want to use MVVM, but with a FlowDocument as my view.)

Paragraph doesn't have a Visibility property. I'm not sure what else to look for.

Answer 1

I had the exact same problem and handled it successfully by wrapping the content of the ListItem in a InlineUIContainer, like so:

  <ListItem>
    <Paragraph>
      <InlineUIContainer>
        <TextBlock x:Name="HideMe" Visibility="Collapsed">
          <Hyperlink NavigateUri="...">Components</Hyperlink>
        </TextBlock>
      </InlineUIContainer>
    </Paragraph>
  </ListItem>

From here you can set the visbility of "HideMe" in code or through a binding.

Answer 2

I tried Chris Bova's answer, but it had a couple problems:

1. Text selection didn't work right
2. The text inside didn't flow like a paragraph

My solution was to add and remove the paragraph from the flow document.

The steps are:

1. Name the flow document (ie flowDocument)
2. Name the item before the paragraph you want to hide (ie previousBlock)
3. Name the paragraph you want to hide (ie hideParagraph)

Then:

        if (<hide paragraph>)
        {
            if (previousBlock.NextBlock == hideParagraph)
            {
                flowDocument.Blocks.Remove(hideParagraph);
            }
        }
        else
        {
            if (previousBlock.NextBlock != hideParagraph)
            {
                flowDocument.Blocks.InsertAfter(previousBlock, hideParagraph);
            }
        }

Answer 3

Options I can think of...

1. Hide the content of the paragraph (don't include the paragraph in your model)
2. Extend Paragraph (or one of its base classes) and provide a dependency property for IsVisible

Answer 4

Set fontsize to 0.004. You can use a style data trigger if necessary.