nsIXULTreeBuilderObserver

nsIXULTreeBuilderObserver
This interface allows clients of the XULTreeBuilder to define domain
specific handling of specific nsITreeView methods that
XULTreeBuilder does not implement.

Methods

canDrop(index, orientation, dataTransfer)

Methods used by the drag feedback code to determine if a drag is allowable at
the current location. To get the behavior where drops are only allowed on
items, such as the mailNews folder pane, always return false whe
the orientation is not DROP_ON.

onDrop(row, orientation, dataTransfer)

Called when the user drops something on this view. The	orientation	param
specifies before/on/after the given	row	.

onToggleOpenState(index)

Called when an item is opened or closed.

onCycleHeader(colID, elt)

Called when a header is clicked.

onCycleCell(row, colID)

Called when a cell in a non-selectable cycling column (e.g.
unread/flag/etc.) is clicked.

onSelectionChanged()

Called when selection in the tree changes

onPerformAction(action)

A command API that can be used to invoke commands on the selection.
The tree will automatically invoke this method when certain keys
are pressed. For example, when the DEL key is pressed, performAction
will be called with the “delete” string.

onPerformActionOnRow(action, row)

A command API that can be used to invoke commands on a specific row.

onPerformActionOnCell(action, row, colID)

A command API that can be used to invoke commands on a specific cell.