I'm showing 30 root items per page on the grid, with a total of 149 pages. But when I click on an item, the PagingToolbar seems to zoom in on the tree starting from that item. That is, the pager shows there's only 1 or 2 pages, depending on the number of child items of the item I clicked on.
The same happens with the Adjacency List example. I set the items per grid page to 5, so that 2 pages are needed to show all root items. But when I click on an item, the pager shows there's only 1 page available.
The TreeGrid is a wonderful piece of equipment, but this shouldn't happen. I'll go dive in the TreeGrid.js file to see if I can tinker with it.