Mastering GUI Programming with Python

Updating the Invoice app for print support

Readers outside the United States almost certainly groaned when we hard-coded the dimensions of our document to 8.5×11, but never fear—we're going to make some changes that will allow us to set the size based on a user's selection of document sizes.

In the InvoiceView class, create the following new method, set_page_size(), to set the page size:

    def set_page_size(self, qrect):        self.doc_width = qrect.width()        self.doc_height = qrect.height()        self.setFixedSize(qtc.QSize(self.doc_width, self.doc_height))        self.document().setPageSize(            qtc.QSizeF(self.doc_width, self.doc_height))

This method will receive a QRect object, from which it will extract width and height values to update the document's settings, ...