Hands-On High Performance Programming with Qt 5

Solution

At first, I suspected that the usage of the rather inefficient QTableWidget class and manually inserting widget items instead of using QTableView would be the culprit, but it turned out to be a totally different problem.

I asked my buddy to make the last few changes to the UI cosmetics and to have a quick look at the slow window loading times. Guess what? The problem didn't even need a profiler. Using the poor man's profiling technique (see Chapter 2, Profiling to Find Bottlenecks, for details), namely, getting a couple of stack traces manually using Process Explorer, the reason for the problem became clear – the resizeToContents() method was being called for the table after each new row had been added. As we can recall from our ...