Bambookit GUI Tutorial
IV. Advanced Features
Chapter 13. Attachments
Attachments are used as a means to 'listen' in on other widgets resize or displacment events and be displaced or resized by an equivalent amount.
attachToWidget, is one widget bieng displaced by the widget it is attached to.
attachToContainer, is one widget changing the size of the widget that 'contains' it, whenever it gets resized.