pygame_sdl2 - app is crashing on mobile during pygame.mouse.get_pressed()

Question

I am developing a game for android with pygame and pygame_sdl2 , and rapt for deploy.

Currently, the game is at a very first stage of development.

I have a joypad draw in the bottom left of my screen, and, when the mouse is pressed in the coordinates of the joypad's buttons, a character is moved according to the button durection. The mouse events are used as touch events as in this (working) example .

The problem is: the game is working on my laptop (I am using Ubuntu), but not on my mobile device. When I start the game, everything shows up as expected, but as soon as I touh the screen (no matter if it's on the buttons or somewhere else), the app goes in background.

My game is in a public github repo if you want to see the whole code (everything relevant is in the main.py file).

I think the error is triggered by the call to pygame.mouse.get_pressed() .

Here is some relevant code which hopefully would help in understanding the problem.

Joypad class (btn_pressed method)

def btn_pressed(self, mouse_event):
    # check if left mouse is being pressed
    if pygame.mouse.get_pressed()[0]:
        x, y  = mouse_event.pos
        if self.btn_up.rect.collidepoint(x, y):
            return 'UP'
        elif self.btn_down.rect.collidepoint(x, y):
            return 'DOWN'
        elif self.btn_left.rect.collidepoint(x, y):
            return 'LEFT'
        elif self.btn_right.rect.collidepoint(x, y):
            return 'RIGHT'

Character class (move method)

def move(self, joypad_direction):
    """
    move the character
    to be used along with Joypad.btn_pressed returns
    ('UP', 'DOWN' 'LEFT', 'RIGHT')
    """

    self.dx = 0
    self.dy = 0

    # check for horizontal move
    if joypad_direction == 'LEFT':
        self.dx = -self.speed
        self.rect.move_ip(-self.speed, 0)
    if joypad_direction == 'RIGHT':
        self.dx = +self.speed
        self.rect.move_ip(self.speed, 0)

    self.dx = 0

    # check for vertical move
    if joypad_direction == 'UP':
        self.dy = -self.speed
        self.rect.move_ip(0, -self.speed)
    if joypad_direction == 'DOWN':
        self.dy = +self.speed
        self.rect.move_ip(0, self.speed)
        self.dy = 0

main loop

while True:

    ev = pygame.event.wait()

    # If not sleeping, draw the screen.
    if not sleeping:
        hero.move(joypad.btn_pressed(ev))
        screen.fill((0, 0, 0, 255))

        joypad.buttons.draw(screen)

        if x is not None:
            screen.blit(hero.image, (x, y))

        pygame.display.flip()

Answer 1

As explained in the comments, there was an issue in my main loop.

I simply had to change my code from:

if not sleeping:
    if not sleeping:
        hero.move(joypad.btn_pressed(ev))

to:

if not sleeping:
    if ev.type == pygame.MOUSEMOTION or ev.type == pygame.MOUSEBUTTONUP:
        hero.move(joypad.btn_pressed(ev))

so that "Joypad class (btn_pressed method)" does not get an error when calling x, y = mouse_event.pos when the event was (eg) QUIT, thus not returning any coordinates (see also the image belowe taken from the pygame's event documentation page ).