RichTextBox inside Expander in WPF

Question

<Expander Header="More options" Margin="281,218,39,12">
    <Button Height="29" Width="111"> hello </Button>
</Expander>

The above code works. But:

<Expander Header="More options" Margin="281,218,39,12">
    <RichTextBox Name="richTextBox1" Margin="100,50,200,30" Height="30" Width="80">
        <FlowDocument>
            <Paragraph>Hi how are you?</Paragraph>
        </FlowDocument>
    </RichTextBox>
</Expander>

This will not work. Why? How to make this work?

Answer 1

Please remove the Margin and avoid setting static Height and Width, it will work.

<Expander Header="More options" >
    <RichTextBox Name="richTextBox1" >
        <FlowDocument>
            <Paragraph>Hi how are you?</Paragraph>
        </FlowDocument>
    </RichTextBox>
</Expander>