Scrollbar Annotation Behavior

• Jul 05, 2019

Overview

You can display scrollbar annotations in a list box control to indicate the following items’ location:

• focused item
• selected items
• checked items (the checked list box control only)
• items corresponding to a search query (a search control should be attached to the list box control)

Supported Controls

• ListBoxControl
• ImageListBoxControl
• CheckedListBoxControl

Options

• Type — a set of flags that specify the enabled annotation types
• Color — the annotation color (the default value depends on the current skin)
• Alignment — the annotation alignment (the default value depends on the current skin)

How to Attach the Behavior in Code

The code below shows how to enable scrollbar annotations for focused and selected rows in an image list box.

C#

using DevExpress.Utils.Behaviors;

behaviorManager1.Attach<ScrollAnnotationsBehavior>(imageListBoxControl1, behavior => {
    behavior.Properties.Type = ScrollAnnotationType.Focus | ScrollAnnotationType.Selection;
});

VB.NET

Imports DevExpress.Utils.Behaviors

behaviorManager1.Attach(Of ScrollAnnotationsBehavior)(imageListBoxControl1, Sub(behavior)
    behavior.Properties.Type = ScrollAnnotationType.Focus Or ScrollAnnotationType.Selection
End Sub)

Tip

You can handle the BaseListBoxControl.CustomDrawScroll event to draw custom annotations for specific scrollbar positions.