Mastering GUI Programming with Python

Using GraphWidget

Our graph widget is finished, so let's head down to MainWindow and use it.

Start by creating your widget and making it the central widget:

        self.graph = GraphWidget(self)        self.setCentralWidget(self.graph)

Next, let's create a method that will read the current CPU usage and send it to GraphWidget. To do this, we'll need to import the cpu_percent function from the psutil library:

from psutil import cpu_percent

Now we can write our graph-updating method as follows:

    def update_graph(self):        cpu_usage = cpu_percent()        self.graph.add_value(cpu_usage)

The cpu_percent() function returns an integer from 0 to 100, reflecting the current CPU utilization on your computer. This is perfect for sending directly to our GraphWidget, whose ...