# ProgressBar (Python)

Marta Maria Casetti
mmcasetti@gmail.com 2012
A widget which indicates progress visually.
Anders Jonsson
anders.jonsson@norsjovallen.se 2018

# ProgressBar

Pressing any key stops and starts this ProgressBar.

This ProgressBar is stopped and started by pressing any key.

# Code used to generate this example

from gi.repository import GLib from gi.repository import Gtk import sys

class MyWindow(Gtk.ApplicationWindow): # a window

def __init__(self, app): Gtk.Window.__init__(self, title="ProgressBar Example", application=app) self.set_default_size(220, 20)

# a progressbar self.progress_bar = Gtk.ProgressBar() # add the progressbar to the window self.add(self.progress_bar)

# the method self.pulse is called each 100 milliseconds # and self.source_id is set to be the ID of the event source # (i.e. the bar changes position every 100 milliseconds) self.source_id = GLib.timeout_add(100, self.pulse)

# event handler # any signal from the keyboard controls if the progressbar stops/starts def do_key_press_event(self, event): # if the progressbar has been stopped (therefore source_id == 0 - see # "else" below), turn it back on if (self.source_id == 0): self.source_id = GLib.timeout_add(100, self.pulse) # if the bar is moving, remove the source with the ID of source_id # from the main context (stop the bar) and set the source_id to 0 else: GLib.source_remove(self.source_id) self.source_id = 0 # stop the signal emission return True

# source function # the progressbar is in "activity mode" when this method is called def pulse(self): self.progress_bar.pulse() # call the function again return True

class MyApplication(Gtk.Application):

def __init__(self): Gtk.Application.__init__(self)

def do_activate(self): win = MyWindow(self) win.show_all()

def do_startup(self): Gtk.Application.do_startup(self)

app = MyApplication() exit_status = app.run(sys.argv) sys.exit(exit_status)

# Useful methods for a ProgressBar widget

Instead of `pulse()`, that makes the bar go back and forth, if we want the ProgressBar to "fill in" a fraction (a `float` between `0.0` and `1.0` included) of the bar that has been completed, use `set_fraction(fraction)`.

To set a text and show it (superimposed over the bar) use `set_text("text")` and `set_show_text(True)`. If a text is not set and `set_show_text(True)` the text will be the percentage of the work that has been completed.

# API-referenser

In this sample we used the following:

GtkProgressBar

GLib - The Main Event Loop

Gdk - Key Values