For Qt 4.6.x, how to auto-size text to fit in a specified width?

Question

Inside of my QGraphicsRectItem::paint(), I am trying to draw the name of the item within its rect(). However, for each of the different items, they can be of variable width

Answer 1

This depends on the range over which you expect your font sizes to vary. If the range is large, incrementing by one may take a long time. If it's just a matter of several point sizes, speed probably won't be an issue.

If the range is large, another approach would be to add a larger interval, instead of '1'. If you exceed the desired size during one step, decrease the interval by, say, half. You'll bounce back and forth across the optimum size by smaller and smaller amounts each time; when the difference between two successive intervals is small, you can quit.

This is similar to the approach used in root finding. It may be overkill, since the size of fonts that will be acceptable to display in a given application is likely to be fairly narrow, and the brute force approach you're already using won't consume much time.