@Bob K Our tabs will work with a page panel. That's in the Demo.
I saw that. That makes it very flexible.
@Bob Keeney Hm...dragging a tab into a different tab panel is doable but challenging.
Before I was trying to create a transparent DragItem with an image blank image (color of the panel's background) and the size of the panel.
As RawData I just passed the ID of the panel. So, when dragged into another panelgroup, it will remove the content from one group and adds it to the new group.
For a "panel receiver" I thought about using a PagePanel. When dragging the DragItem over the "receiver", it checks if the UTI matches. I set the UTI of the dragitem to be something that can hold a dynamic groupType name. So, I can somehow make some PanelGroups accept certain panels, and refuse others, that don't match the groupType.
That way I can keep property panels together with other property panels... and panels I use for viewers or editors together with other viewers and editors.
What I try to make is a Subtitle Editor. I had one that works with SRT and Netflix in the past. But want to make a better one. One that has more the look and feel of software most video editors use. I use Premiere. So, I want to get the look and feel of the Adobe software to make it easier to use for people already familiar with that software.
Of course it will not be a 100% match. But close enough.
A timeline will be one type of PanelGroup. Caption, Track and Project property panels will be another. And a third group would be the viewer, with a captioned-video display (a canvas showing the current frame, with caption, timecode, safe-area overlays, etc)