Unsolved How to modify tabs width in QPdfWriter?

[alsa]

After declare a QPdfWriter object, I write in it using QPainter; my problem is data to be write in are in a table form, and items of each line are separated from a tab.
If an item is larger than space of a tab, it keeps more space and the last item of the line could be placed out of paper.
How can I reduce the tab Width to avoid this?