I have a custom NSTableRowView implementation to display my data cells. The table also contains group rows using a simple NSTextField.
In my custom row view I need to change the drawing of the bottom separator slightly depending on if the next row below is a data cell (i.e. my custom row) or a group header.
In the case of a group header I don’t have to draw the separator, otherwise I’ll end up with a 2px separator like shown in the screenshot.
Is there a way to get a reference to the next (or previous) NSTableRowView instance from [NSTableRowView drawBackgroundInRect:...]?

Am I correct that your table view delegate implements
-tableView:rowViewForRow:?If so, let the table view delegate help:
drawsSeparatorto your custom row class.drawRectand adjust your drawing accordingly.drawsSeparatoron your row inrowViewForRow. You can invoke-tableView:isGroupRow:withrow + 1to determine whether the next row is a group (after checking to make sure you’re not on the last row).