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I have a ListBox that contains two columns - column one contains a Toggle Button, column two contains an Expander with multiple controls within it. If the expander is collapsed, the overall scrolling of the ListBox works fine. However, if the Expander is open and the expander contains a large quantity of items, the ListBox will scroll the entire row size, often not showing part of the expander list.

This would be similar to placing an image in the list box that is larger than the viewable area of the list box. In this case, if you click the scrollbar, you would want to "step" down the image, without it scrolling off the screen in one click.

Is there a setting for the ListBox that will allow the partial scrolling as I've described? My listBox is defined in a xaml, the controls are added via C# code.

spajce
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gmletzkojr
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1 Answers1

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Have you tried turning on smooth scrolling by setting ScrollViewer.CanContentScroll to false? This is what controls whether the ScrollViewer will scroll an item at a time, or smoothly with partial items available.

"ScrollViewer currently allows two scrolling modes: smooth pixel-by-pixel scrolling (CanContentScroll = false) or discrete item-by-item scrolling (CanContentScroll = true). Currently WPF supports UI virtualization only when scrolling by item. Pixel-based scrolling is also called 'physical scrolling' and item-based scrolling is also called 'logical scrolling'." (From this answer).

If you have a lot of items in your ListBox, this may not be an ideal solution, however, because it turns off Virtualization, and therefore may have a performance impact. Take a look at this answer to see more about smooth scrolling and virtualization. (One answer suggests a hack that allows for smooth scrolling and virtualization).

Community
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Brian S
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