# ExpandableContentUI class

Namespace: [Rhino.UI.Controls](https://developer.rhino3d.com/api/rhinocommon/namespace/rhino.ui.controls.md) · Assembly: [RhinoCommon](https://developer.rhino3d.com/api/rhinocommon/assembly/rhinocommon.md)

```cs
public class ExpandableContentUI : ContentUI, IDisposable
```

This class extends ContentUI to represent the default user interface which the RDK provides for a content.This is the UI created by the default implementation of CRhRdkCoreContent::CreateUI(). The main feature of this implementation is a 'holder' containing one or more expandable 'sections' (AKA 'roll-ups').

## Methods

- [AddSection](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.expandablecontentui/addsection.md): (2 overloads) Add a section to the UI with a custom controller. Called \e before Create().

## Inherited Members

- From [ContentUI](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui.md): [m_cpp](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/m-cpp.md), [CppPointer](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/cpppointer.md), [ContentUIHolder](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/contentuiholder.md), [Dispose](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/dispose.md), [EditorUuid](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/editoruuid.md), [IsCreated](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/iscreated.md), [IsShown](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/isshown.md), [Uuid](https://developer.rhino3d.com/api/rhinocommon/type/rhino.ui.controls.contentui/uuid.md)