Sets image as the image to be used for all list entries containing sublisttags that are in an expanded state in an outline list dialog item dlgitem (unless overridden by a specific open branch image setting for a particular listtag list entry) in window window. The image appears at the front of all the list entries that contain sublisttags that are expanded. Use dlgitem_set_default_openbranch_image to set the default image for list items that have children and are expanded. If you were to create a file browser using an outline list, you may use a open folder icon as your default open branch image. If dlgitem does not refer to an outline list item, $ERROR is set and zero ( 0) is returned. Otherwise, one (1) is returned.

The window parameter is a window identifier. dlgitem is the value of the control's id attribute.

Example:

This sets the image for all list entries containing sublists and that are expanded in the outline list item OutlistItem to the Openfolder image.