NSTableView get rid blank space separating columns

Question

I have an NSTableView with 4 columns. I also have a custom background color for each row. The only problem is I have these ugly white spaces where the gridlines would go in both the horizontal and vertical axis. I have both unchecked in IB, but they still show up. How can I get rid of the vertical ones and change the color and size of the horizontal ones?

Here's what I see:

Answer 1

You'll need to override drawClipInRect to draw your own grid. The article I linked to modifies it so it only draws vertical gridlines. You'll have to modify it to only draw horizontal ones instead, but the basic strategy is the same: By overriding it, you can make it not draw vertical lines by simply not including the code for it.