QProgressBar PyQt5

Question

I have a QPushButton which when clicked runs a function to plot a graph.

I want a progressbar below that QPushButton showing busy indicator. I dnt want the percentage or any logic in the bar just the looping type bar we get by setting -

self.progressbar.setMinimum(0)
self.progressbar.setMaximum(0)

I dnt want this bar to show in the UI initially so i have set-

self.progressbar.setVisible(False)

And then this to show the bar:

def functiontoplotgraph(self):
    self.progressbar.setVisible(True)
    ---#code to plot graph
    self.progressbar.hide()

My problem is the bar shows after the data is plotted. i want it to show when i click the button and hide when plot is shown.

Answer 1

Import QApplication and call QApplication.processEvents() immediately after self.progressbar.setVisible(True) .

The reason is that many actions are not done immediately as you call them in code (typically showing/hiding/resizing/layouting) but are queued in even queue. By calling processEvents() you will force to do them right away. So I assume this should help.

In some cases you should also try QApplication.sendPostedEvents() before processEvents() .