Nested Grouping in Layer Tree

[neumann]

It would be nice if we could have more than one group level (nested groups) in the layer tree. It would allow better structuring of more complex projects. If group opacity (#1898) is also implemented it would allow for better symbology in complex projects.

[pcav]

I think this would be more complex than average uses could bear

[Donkagen2]

I find the lack of nested groups in projects with lots of layers to be a significant shortfall, especially when using QGIS to explain something to observers... I'm continually hunting for the correct layers to turn on and off. Nesting is the same model that everyone uses with directories to handle this complexity so should be intuitive for most users.

[lutra]

I agree, I feel the same necessity for a more complex legend structure and the same is asked by the vast majority of the users that approach QGIS. Together with the lack of multiple selection of layers in the legend and with the lack of an option to "add as group" when adding vectors/rasters (tickets already exist for both issues), is one of more important tasks to be accomplished to improve qgis usability.

Meanwhile I'll add this ticket to the list of the ones possibly to be discussed in the next developer meeting.

Replying to Donkagen2:

I find the lack of nested groups in projects with lots of layers to be a significant shortfall, especially when using QGIS to explain something to observers... I'm continually hunting for the correct layers to turn on and off. Nesting is the same model that everyone uses with directories to handle this complexity so should be intuitive for most users.

[jef]

The patch also contains support for nested layers in the QGIS mapserver. Please review.

[neumann]

Thank you Jürgen, for providing this patch!

I had a brief test (only the desktop), not the QGIS mapserver. It seems to work fine. There is one usability issue, though: if you want to add a new group to an already selected group (potentially deeply nested), the newly added group is always added to the very bottom. It would be nice if the newly added group would be added to the currently active (selected) group, not to the very bottom. I don't know how complicated this would be to fix?

Should I report this as a separate issue? It is not directly related to the nested grouping patch, but the issue already existed before.

[neumann]

Further testing revealed another, more serious issue:

when removing the parent group of a nested group (e.g. 2 other groups nested within a parent) with a right-click "Remove", QGIS hangs/crashes.

This happens on Ubuntu Lucid 64bit with QT 4.6.2

[jef]

Replying to neumann:

when removing the parent group of a nested group (e.g. 2 other groups nested within a parent) with a right-click "Remove", QGIS hangs/crashes.

fixed in the new patch.