Theoretically, it is possible to construct a PanelBar from an already existing instance, and append items via the widget's API:
However, it will be a lot easier
to create the PanelBar only after you have its items, and not before that. If you prefer to have an empty widget visible to the user initially, the you can destroy it and create a new instance on the same place.
On a side note, please avoid posting duplicate forum threads, thank you.
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