Printing (PDF)

Would you believe that we have new requirements? They are as follows:

• Req 25: BigProject shall be able to generate a report of temperature readings for the last 24 hours.
• Req 26: The report shall be output in PDF format.

Qt to the rescue!

Qt provides printing capabilities, including the ability to output to a PDF file! We will make use of it here.

The basics

While some Qt GUI objects have special print methods that can be invoked to print on QPrinter, many don't. This is because of how Qt chose to support printing.

At the base level, Qt paints GUI objects onto paint devices. When a widget is drawn on the screen, Qt is painting it onto the screen. Printing works essentially the same way. Objects are painted...