Creating a Pygame window


Feb. 1, 2010 Code on Github

In this first tutorial, we'll cover the basics and write some boilerplate code for Pygame - code you will almost always write whenever you use Pygame. We will:

  • Create a Pygame window
  • Stop the window from immediately disappearing
  • Close the window in response to a quit event
  • Change the title and background colour of the window

The Pygame window

Since we are going to use the Pygame module, the first thing we need to do is import it.

import pygame

We can now create a Pygame window object (which I've called 'screen') using pygame.display.set_mode(). This object requires two values that define the width and height of the window. Rather than use constants, we'll define two variables, width and height, which will make the program easier to change later on. Feel free to use any integers that suit you. In order to display the window, we use the flip() function:

(width, height) = (300, 200)
screen = pygame.display.set_mode((width, height))
pygame.display.flip()

If you now run this program, you’ll see a 300 x 200 pixel window appear and then promptly disappear. The problem is that once as the flip() function has been called, the end of the code is reached, so the program ends.

To keep the screen visible for as long as we want, we need to make sure the program doesn't end. We could do this by adding an infinite loop.

while True:
  pass

The problem with an infinite loop is that, by definition, it never ends. The program won't quit even if we want it to. If we try to close the window by clicking on the X, nothing happens. You have to use Ctrl + C in the command line to force the program to quit.

Closing the window

We want our window to persist until the user chooses to closes it. To achieve this, we monitor user inputs (known as 'events') using pygame.event.get(). This function returns a list of events which we can loop through and check to see whether any have the type QUIT. If we find such an event, we exit our loop, which is best done by changing a boolean variable (which I've called 'running').

running = True
while running:
  for event in pygame.event.get():
    if event.type == pygame.QUIT:
      running = False

The window now persists whilst 'running' is equal to True, which it will be until you close the window (by clicking the X). Note that if you use an IDE for Python programming, then it may interfere with Pygame. This isn’t normally a major problem but it can stop the Pygame window from closing properly. If so, adding pygame.quit() should solve the problem (Thanks to nf3 in the comments for mentioning this).

Changing the window's properties

Now we have a usable window, we can change its properties. For example, we can change its title using the set_caption() function.

pygame.display.set_caption('Tutorial 1')

We can change the background colour by filling the screen object. Colours are defined using a 3-tuple of integers from 0 to 255, for the red, green and blue values respectively. For example, white is (255,255,255). Changes need to be made before the flip() function is called.

background_colour = (255,255,255)
screen.fill(background_colour)

The final program

The complete program, after a bit of rearrangement, should now look like this:

import pygame

background_colour = (255,255,255)
(width, height) = (300, 200)

screen = pygame.display.set_mode((width, height))
pygame.display.set_caption('Tutorial 1')
screen.fill(background_colour)

pygame.display.flip()

running = True
while running:
  for event in pygame.event.get():
    if event.type == pygame.QUIT:
      running = False

You can also find the complete code for this tutorial by clicking the Code on Github link at the top of the article.

Running the program should create a window that looks like this (on Windows XP).

It's not very exciting at the moment, but now we have a window that persists until we close it. In the next tutorial we'll draw some shapes in our window and start our simulation by creating a Particle object.

An empty Pygame window

Comments (13)

nf3 on Jan. 28, 2011, 11:51 a.m.

found your tutorial very useful and easy to follow.

As i code with Idle, was troubled with the bad closing habits of the app. After a internet search I found a simple unobstrusive solution:

after, and outside of the last 'while running' loop, place the instruction

pygame.quit ()

peter on Jan. 28, 2011, 12:08 p.m.

Cool. The closing error was the main reason I've avoided using an IDE. I might give it a go now, thanks.

Salvenheit on Dec. 29, 2011, 5:07 p.m.

Perfectly explained, convenient tools to get the code and graphically nice site. It is helping me a lot, thank you very much.

Aditya Sriram on March 2, 2013, 12:24 p.m.

Why is it that we use

pygame.display.set_caption()
pygame.display.flip()

and not

screen.set_caption()
screen.flip()

Like the website very much. Glad to see that I'm not the only one using Windows XP.

William on Nov. 18, 2013, 7:01 a.m.

Hi Peter
I love your work! I am a physics technician and your star formation simulation programme is proving very popular with the teachers.It works without problem on the Raspberry Pi, but when I try to use it on a windows machine with Python 2.7.6 installed, it throws up an error "Traceback (most recent call last): File "C:\Python27\window_opening.py", line 1, in <module> import pygame File "C:\Python27\lib\pygame.py", line 1 /* ^SyntaxError: invalid syntax"Should I install an earlier version, if so, which one? Thank you

peter on Nov. 20, 2013, 6:02 p.m.

Hi William,

That's very cool that it works on Raspberry Pi. I'm glad you're enjoying the program. I have a 3D version online at Khan Academy if you're interested: https://www.khanacademy.org/cs/challenge-modeling-accretion-disks/1180451277

As for the problem you're having, it looks like there's a problem with the pygame.py file. Have you tried running any other programs that use Pygame or running python in the command line and typing import pygame? I'll check what the pygame file looks like on my Windows machine and see if I can work out what might be wrong, but it seems unlikely that I will be able to. I wrote the program using Python 2.7, so that's not the problem.

If you have any other problems, you can email me using the Contact Me button on the left hand side of the page.

Iavor on March 30, 2015, 5:20 a.m.

Hi Peter,

I noticed that your code does not initialize PyGame after the import statement (pygame.init()) before making and displaying the screen. My 300 by 200 PyGame screen does not show up unless I have this line in my code and I was wondering how you got it to work without it.

Iavor

Anonymous on July 18, 2015, 6:04 a.m.

Hello Peter,

Thank you very much for this tutorial, I am enjoying it.

Just one minor question: to check if an event is an object of type pygame.QUIT, why can't I use type(event) instead of event.type?

D P Robindon on Nov. 8, 2016, 6:11 a.m.

Thank you, I've been wondering how to do this for some time and now I know. Time to make some games. Thanks again!

Kykex on March 5, 2017, 6:07 a.m.

Hi, how did you get the code with that style? Looks great and I would like to know to use it in a future project.

Martin on Sept. 18, 2017, 6:19 a.m.

Hello Peter,

Thank you for an amazing pygame tutorial. I was googleing pygame and happened upon your page. Thanks to your great physics tutorials, I was able to create my project in nontime. Thank you for the great work.

Thank you,

Martin

Sagisu on Nov. 5, 2017, 3:47 a.m.

Hi Peter, Very good Web Page for python & pygame.

formal Python & pygame homepage. not understandable

I dont understand guess

Implicit expression and omit expression Python computer lagnguage.becouse what is omit is not able to recognize and guess easily.

your Page is very good .I'm glad to access this site and I hope that continue like this your site for long time. May I ask some question ? What is it mean "WhiteSpace" ?

November 05th ,2017 with regard.

Anonymous on Dec. 30, 2017, 2:35 a.m.

How do you creat a smaller screen on top of the orginal screen in pygame?

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