Button area having a mixed state button for collapsing and expanding user interface items

摘要

A method of indicating expanded states and collapsed states of lower level expander/collapser items in a higher level visual control of a user interface display. The method includes providing, in the higher level visual control, a lower level expander/collapser indicator area; displaying a first display in the expander/collapser indicator area when all the lower level expander/collapser items are in a first state; displaying a second different display in the expander/collapser indicator area when all of the lower level expander/collapser items are in a second different state; and displaying a third different display in the expander/collapser indicator area when a first one of the lower level expander/collapser items is in the first state and a second one of the lower level expander/collapser items is not in the first state.