In UIXTreeTable the focusRowKey attribute specifies the rowKey of the currently focused row. In the renderer, the row with the focusRowKey is rendered as the root node of the TreeTable and a focus path is rendered above the TreeTable.
When no focusRowKey attribute is specified on the component, UIXTreeTable defaults the focusRowKey to the first node in the treeModel. So the focusRowKey can never be null. This defaulting of the focusRowKey is OK for UIXTreeTable because it only supports a single root node. The issue I have with this is that I want to support multi-rooted TreeTables. So I want to do two things: 1) When no focusRowKey attribute is specified on the component, I will render all of the root nodes in the TreeTable (multi-rooted TreeTable). 2) When a focusRowKey attribute is specified, I will render the row with the focusRowKey as the single root node of the TreeTable. Unfortunately, becuase UIXTreeTable always sets a default focusRowKey, I can't achieve #1 above. The defaulting of the focusRowKey is done in the _init() method of UIXTreeTable, which is a package scoped method. So I can't override this default behavior in my subclass of UIXTreeTable. There are a couple of solutions to this: 1) Move the defaulting logic to a protected method in the UIXTreeTable so that it can be overriden in subclasses 2) Move the defaulting logic out of the component and into the renderer. I hope all of this makes sense, and any input on this is very much appreciated. -- Kamran
