Mastering GUI Programming with Python

Building a disk usage chart

The first chart we'll create is a bar chart for displaying the disk space used by each storage partition on the computer. Each detected partition will have a bar indicating what percentage of its space is being used.

Let's start by creating a class for the chart:

class DiskUsageChartView(qtch.QChartView):    chart_title = 'Disk Usage by Partition'    def __init__(self):        super().__init__()

The class is subclassed from the QtChart.QChartView class; this subclass of QGraphicsView is a widget that can display QChart objects. Just like the Qt graphics framework, the QtChart framework is based on a model-view design. In this case, the QChart object is analogous to a QGraphicsScene object, which will be attached to the QChartView ...