Mastering GUI Programming with Python

Building a GraphWidget

Our CPU monitor will display real-time CPU activity using an area graph. The graph will be enhanced by a color gradient, which will show higher values in a different color from lower values. The graph will only show a configured number of values at one time, scrolling old values off to the left side of the widget as new ones are added from the right.

To accomplish this, we need to build a custom widget. We'll call it GraphWidget, and begin it as follows:

class GraphWidget(qtw.QWidget):    """A widget to display a running graph of information"""    crit_color = qtg.QColor(255, 0, 0)  # red    warn_color = qtg.QColor(255, 255, 0)  # yellow    good_color = qtg.QColor(0, 255, 0)  # green    def __init__(        self, *args, data_width=20, minimum=0, ...