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6.9: Checking for Keyboard Presses

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               elif event.type == KEYDOWN:
                    if event.key == K_q:
                        clickedButton = YELLOW
                    elif event.key == K_w:
                        clickedButton = BLUE
                    elif event.key == K_a:
                        clickedButton = RED
                    elif event.key == K_s:
                        clickedButton = GREEN

    Lines 1 [85] to 9 [93] check for any KEYDOWN events (created when the user presses a key on the keyboard). The Q, W, A, and S keys correspond to the buttons because they are arranged in a square shape on the keyboard.

    The Q key is in the upper left of the four keyboard keys, just like the yellow button on the screen is in the upper left, so we will make pressing the Q key the same as clicking on the yellow button.

    We can do this by setting the clickedButton variable to the value in the constant variable YELLOW. We can do the same for the three other keys. This way, the user can play Simulate with either the mouse or keyboard.

    This page titled 6.9: Checking for Keyboard Presses is shared under a CC BY-NC-SA 3.0 license and was authored, remixed, and/or curated by Al Sweigart via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.