Base class for Box containers. Base class for Box containers. It arranges children controls vertically or horizontally, and rearranges them automatically when their minimum size changes. Add a control to the box as a spacer. If [i]begin[/i] is true the spacer control will be inserted in front of other children. Return the alignment of children in the container. Set the alignment of children in the container(Must be one of ALIGN_BEGIN, ALIGN_CENTER or ALIGN_END). Align children with beginning of the container. Align children with center of the container. Align children with end of the container.