| Interface | Description | 
|---|---|
| Layout.AnimationCallback | Callback interface used by  Layout.layout(int, AnimationCallback)to provide updates on animation progress. | 
| Class | Description | 
|---|---|
| Layout | Helper class for laying out a container element and its children. | 
| LayoutImpl | Default implementation, which works with all browsers except for IE6. | 
| LayoutImplIE8 | This implementation is used on IE8. | 
| Enum | Description | 
|---|---|
| Layout.Alignment | Used to specify the alignment of child elements within a layer. |