> For the complete documentation index, see [llms.txt](https://docs.flatredball.com/gum/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.flatredball.com/gum/code/events-and-interactivity/scrolling.md).
# Scrolling
## Introduction
Gum includes controls which have built-in scrolling support. These are:
* `ListBox`
* `ItemsControl`
* `ScrollViewer`
Both `ListBox` and `ItemsControl` inherit from `ScrollViewer`, so many of the properties for scrolling are the same across all controls.
## Built-In Scrolling Behavior
All controls support the following built-in actions for scrolling:
* Mouse/touch screen interactions with scroll bars
* Mouse wheel scrolling
* Touch screen swipe scrolling
## Scrolling Speed
Scrolling speed is controlled by the following two variables:
* `SmallChange` - The amount to scroll when a scroll bar button is clicked, or when a *tick* is scrolled on the mouse wheel
* `LargeChange` - The amount to scroll when the user clicks on the scroll bar track
The following code creates two `ListBoxes` to compare the scrolling speed of each.
```csharp
// Initialize
var defaultListBox = new ListBox();
defaultListBox.AddToRoot();
defaultListBox.Anchor(Anchor.Center);
defaultListBox.X = -100;
for (int i = 0; i < 20; i++)
{
defaultListBox.Items.Add(i);
}
var fastListBox = new ListBox();
fastListBox.AddToRoot();
fastListBox.Anchor(Anchor.Center);
fastListBox.X = 100;
// default is 10:
fastListBox.SmallChange = 50;
for (int i = 0; i < 20; i++)
{
fastListBox.Items.Add(i);
}
```
Two ListBoxes with different SmallChange values
---
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