Synchronizing Two Rich Text Box Scroll bars in WPF

Question

I have researched ways of synchronizing scroll bars for rich text boxes but have only come across solutions or methods for Winforms but these do not work in WPF application. If anyone has done this in WPF and could provide some direction/code/guidance in how to go about implementing this, it will be greatly appreciated. I am new to WPF so any help is welcomed. Thanks.

possible duplicate of [Synchronized scrolling of two ScrollViewers whenever any one is scrolled in wpf](http://stackoverflow.com/questions/15151974/synchronized-scrolling-of-two-scrollviewers-whenever-any-one-is-scrolled-in-wpf) — Rohit Vats, Jan 01 '14 at 09:36

score 8 · Accepted Answer · edited May 23 '17 at 12:00

You can use the ScrollViewer.ScrollChanged routed event to listen for scrolling changes. Example:

<UniformGrid Rows="1" Width="300" Height="150" >
    <RichTextBox x:Name="_rich1" 
                 VerticalScrollBarVisibility="Auto"
                 ScrollViewer.ScrollChanged="RichTextBox_ScrollChanged" />
    <RichTextBox x:Name="_rich2" 
                 VerticalScrollBarVisibility="Auto"
                 ScrollViewer.ScrollChanged="RichTextBox_ScrollChanged" />
</UniformGrid>

Then, in the event handler you do the actual synchronizing (code ~~stolen from~~ inspired by this other answer):

private void RichTextBox_ScrollChanged(object sender, ScrollChangedEventArgs e)
{
    var textToSync = (sender == _rich1) ? _rich2 : _rich1;

    textToSync.ScrollToVerticalOffset(e.VerticalOffset);
    textToSync.ScrollToHorizontalOffset(e.HorizontalOffset);
}

Synchronizing Two Rich Text Box Scroll bars in WPF

1 Answers1