# EVENT_EXPAND

Object Types: Trees.

Description: Expand events are sent to the callback function associated with the tree control when the user expands a tree item. To expand items, users can click the plus sign next to the tree item, press the right arrow, and right-click and select Expand Subtree or Expand All.

Event Data Parameters:

Right-clicking and selecting Expand All: eventData1 = VAL_ALL
eventData2 = 0

Right-clicking and selecting Expand Subtree: eventData1 = VAL_DESCENDENT
eventData2 = itemIndex

Clicking the plus sign or pressing the right arrow: eventData1 = 0
eventData2 = itemIndex

This event is swallowable. Return 1 to swallow EVENT_EXPAND.