Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
429 views
in Technique[技术] by (71.8m points)

python - Pygame button single click


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

There are several things that should be changed:

The drawing and button code shouldn't be in the event loop but in the outer while loop. You're calling the button function every time an event occurs (for example if the mouse moves).

The button function is doing too much. It creates and blits text surfaces, draws rects, checks for collisions and calls the click method.

You shouldn't use pygame.mouse.get_pressed() and instead handle the MOUSEBUTTONDOWN events in the event loop. mouse.get_pressed just checks if a mouse button is held and not if a single click occurred.

I'll just show you an easy solution without a function and with a rect as the button here. I handle the collision and update the number in the event loop. If you want to create several buttons, I'd suggest to rewrite it in an object-oriented manner (I can show you an example if you want).

import pygame


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

WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
GRAY = (30, 30, 30)
FONT = pygame.font.Font("freesansbold.ttf", 50)


def loop():
    clock = pygame.time.Clock()
    number = 0
    # The button is just a rect.
    button = pygame.Rect(0, 100, 200, 200)
    done = False
    while not done:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                done = True
            # This block is executed once for each MOUSEBUTTONDOWN event.
            elif event.type == pygame.MOUSEBUTTONDOWN:
                # 1 is the left mouse button, 2 is middle, 3 is right.
                if event.button == 1:
                    # `event.pos` is the mouse position.
                    if button.collidepoint(event.pos):
                        # Increment the number.
                        number += 1

        screen.fill(WHITE)
        pygame.draw.rect(screen, GRAY, button)
        text_surf = FONT.render(str(number), True, BLACK)
        # You can pass the center directly to the `get_rect` method.
        text_rect = text_surf.get_rect(center=(width/2, 30))
        screen.blit(text_surf, text_rect)
        pygame.display.update()

        clock.tick(30)


loop()
pygame.quit()

Addendum: I recommend using a object-oriented solution with a Button class that is a subclass of pygame.sprite.Sprite and can be added to sprite groups. You can pass your own images to the Button class or use the default images. You also have to pass a callback function or method to each button instance which will get called in the handle_event method to update the specific attributes of the game class (here I have a method that increments a counter and another one to quit the game).

import pygame as pg


pg.init()
screen = pg.display.set_mode((800, 600))
FONT = pg.font.SysFont('Comic Sans MS', 32)
# Default button images/pygame.Surfaces.
IMAGE_NORMAL = pg.Surface((100, 32))
IMAGE_NORMAL.fill(pg.Color('dodgerblue1'))
IMAGE_HOVER = pg.Surface((100, 32))
IMAGE_HOVER.fill(pg.Color('lightskyblue'))
IMAGE_DOWN = pg.Surface((100, 32))
IMAGE_DOWN.fill(pg.Color('aquamarine1'))


# Button is a sprite subclass, that means it can be added to a sprite group.
# You can draw and update all sprites in a group by
# calling `group.update()` and `group.draw(screen)`.
class Button(pg.sprite.Sprite):

    def __init__(self, x, y, width, height, callback,
                 font=FONT, text='', text_color=(0, 0, 0),
                 image_normal=IMAGE_NORMAL, image_hover=IMAGE_HOVER,
                 image_down=IMAGE_DOWN):
        super().__init__()
        # Scale the images to the desired size (doesn't modify the originals).
        self.image_normal = pg.transform.scale(image_normal, (width, height))
        self.image_hover = pg.transform.scale(image_hover, (width, height))
        self.image_down = pg.transform.scale(image_down, (width, height))

        self.image = self.image_normal  # The currently active image.
        self.rect = self.image.get_rect(topleft=(x, y))
        # To center the text rect.
        image_center = self.image.get_rect().center
        text_surf = font.render(text, True, text_color)
        text_rect = text_surf.get_rect(center=image_center)
        # Blit the text onto the images.
        for image in (self.image_normal, self.image_hover, self.image_down):
            image.blit(text_surf, text_rect)

        # This function will be called when the button gets pressed.
        self.callback = callback
        self.button_down = False

    def handle_event(self, event):
        if event.type == pg.MOUSEBUTTONDOWN:
            if self.rect.collidepoint(event.pos):
                self.image = self.image_down
                self.button_down = True
        elif event.type == pg.MOUSEBUTTONUP:
            # If the rect collides with the mouse pos.
            if self.rect.collidepoint(event.pos) and self.button_down:
                self.callback()  # Call the function.
                self.image = self.image_hover
            self.button_down = False
        elif event.type == pg.MOUSEMOTION:
            collided = self.rect.collidepoint(event.pos)
            if collided and not self.button_down:
                self.image = self.image_hover
            elif not collided:
                self.image = self.image_normal


class Game:

    def __init__(self, screen):
        self.done = False
        self.clock = pg.time.Clock()
        self.screen = screen
        # Contains all sprites. Also put the button sprites into a
        # separate group in your own game.
        self.all_sprites = pg.sprite.Group()
        self.number = 0
        # Create the button instances. You can pass your own images here.
        self.start_button = Button(
            320, 70, 170, 65, self.increment_number,
            FONT, 'Increment', (255, 255, 255),
            IMAGE_NORMAL, IMAGE_HOVER, IMAGE_DOWN)
        # If you don't pass images, the default images will be used.
        self.quit_button = Button(
            320, 240, 170, 65, self.quit_game,
            FONT, 'Quit', (255, 255, 255))
        # Add the button sprites to the sprite group.
        self.all_sprites.add(self.start_button, self.quit_button)

    def quit_game(self):
        """Callback method to quit the game."""
        self.done = True

    def increment_number(self):
        """Callback method to increment the number."""
        self.number += 1
        print(self.number)

    def run(self):
        while not self.done:
            self.dt = self.clock.tick(30) / 1000
            self.handle_events()
            self.run_logic()
            self.draw()

    def handle_events(self):
        for event in pg.event.get():
            if event.type == pg.QUIT:
                self.done = True
            for button in self.all_sprites:
                button.handle_event(event)

    def run_logic(self):
        self.all_sprites.update(self.dt)

    def draw(self):
        self.screen.fill((30, 30, 30))
        self.all_sprites.draw(self.screen)
        pg.display.flip()


if __name__ == '__main__':
    pg.init()
    Game(screen).run()
    pg.quit()

Addendum 2: A intermediate solution with buttons as dictionaries. It would also be possible to use lists, but dictionaries are more readable.

import pygame


pygame.init()

WHITE = (255, 255, 255)
ACTIVE_COLOR = pygame.Color('dodgerblue1')
INACTIVE_COLOR = pygame.Color('dodgerblue4')
FONT = pygame.font.Font(None, 50)


def draw_button(button, screen):
    """Draw the button rect and the text surface."""
    pygame.draw.rect(screen, button['color'], button['rect'])
    screen.blit(button['text'], button['text rect'])


def create_button(x, y, w, h, text, callback):
    """A button is a dictionary that contains the relevant data.

    Consists of a rect, text surface and text rect, color and a
    callback function.
    """
    # The button is a dictionary consisting of the rect, text,
    # text rect, color and the callback function.
    text_surf = FONT.render(text, True, WHITE)
    button_rect = pygame.Rect(x, y, w, h)
    text_rect = text_surf.get_rect(center=button_rect.center)
    button = {
        'rect': button_rect,
        'text': text_surf,
        'text rect': text_rect,
        'color': INACTIVE_COLOR,
        'callback': callback,
        }
    return button


def main():
    screen = pygame.display.set_mode((640, 480))
    clock = pygame.time.Clock()
    done = False

    number = 0

    def increment_number():  # A callback function for the button.
        """Increment the `number` in the enclosing scope."""
        nonlocal number
        number += 1
        print(number)

    def quit_game():  # A callback function for the button.
        nonlocal done
        done = True

    button1 = create_button(100, 100, 250, 80, 'Click me!', increment_number)
    button2 = create_button(100, 200, 250, 80, 'Me too!', quit_game)
    # A list that contains all buttons.
    button_list = [button1, button2]

    while not done:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                done = True
            # This block is executed once for each MOUSEBUTTONDOWN event.
            elif event.type == pygame.MOUSEBUTTONDOWN:
                # 1 is the left mouse button, 2 is middle, 3 is right.
                if event.button == 1:
                    for button in button_list:
                        # `event.pos` is the mouse position.
                        if button['rect'].collidepoint(event.pos):
                            # Increment the number by calling the callback
                            # function in the button list.
                            button['callback']()
            elif event.type == pygame.MOUSEMOTION:
                # When the mouse gets moved, change the color of the
                # buttons if they collide with the mouse.
                for button in button_list:
                    if button['rect'].collidepoint(event.pos):
                        button['color'] = ACTIVE_COLOR
                    else:
                        button['color'] = INACTIVE_COLOR

        screen.fill(WHITE)
        for button in button_list:
            draw_button(button, screen)
        pygame.display.update()
        clock.tick(30)


main()
pygame.quit()

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...