Why won't my button change color when i hover over it pygame?

Question

I\'m new to pygame and have been attempting to create a simple interface with some buttons. I can\'t get the button to change color when the mouse hovers over it.

I\'ve

Answer 1

There are a lot of problems with your code, and would like to suggest a less verbose way to code this using pygame.Rect instead of pygame.Sprite, as it does not require as much understanding of game design and is an inheritance-free approach.

Firstly we create the button class:

import pygame
import sys

class Button:
    def __init__(self, rect, default_colour=(0,255,0), hovered_colour=(255,0,0), text="", font=None): #using default arguments
        self.rect = pygame.Rect(rect)

        self.default_colour = default_colour
        self.hovered_colour = hovered_colour

        self.font = font if font else pygame.font.Font(None, 20) #initialise/import font
        self.text = self.font.render(text, True, (0,0,0)) #render text

    def draw(self, surf, mouse_coords):
        if self.hover(mouse_coords):
            pygame.draw.rect(surf, self.hovered_colour, self.rect, 0)
        else:
            pygame.draw.rect(surf, self.default_colour, self.rect, 0)

        surf.blit(self.text, self.text.get_rect(center=self.rect.center)) #rect has a centre attribute

    def hover(self, mouse):
        mouse_rect = pygame.Rect(mouse, [1,1]) #using inbuilt collision function
        return mouse_rect.colliderect(self.rect) #returns a boolean, no need to do this: if mouse_rect.colliderect(self.rect): return True, else: return False 

then we write the main program loop (continues on from previous block of code)

pygame.init()
screen = pygame.display.set_mode([500,500])

def response1(): #callback function when button 1 is pressed
    print("Button 1 pressed")

def response2(): #callback function when button 2 is pressed
    print("Button 2 pressed")

def main(buttons):
    while True: #setting a variable to True is unnecessary as you can just use "break" to exit the loop.
    #this is only not the case in rare cases

        screen.fill((255,255,255)) #unneccessary to put in another function

        for event in pygame.event.get(): #only 1 event loop required
            if event.type == pygame.QUIT:
                pygame.quit()
                sys.exit()

            elif event.type == pygame.MOUSEBUTTONDOWN:
                for button in buttons: 
                    if button["button"].hover(pygame.mouse.get_pos()):
                        button["func"]() #calls function if clicked on

        for button in buttons: #draws all buttons in array, can be optimised to not occur when user clicks
            button["button"].draw(screen, pygame.mouse.get_pos())

        pygame.display.flip() #update the surface at the end of the loop instead of the beginning
    #only use pygame.display.update(rect=None) to update a specific portion of the display, otherwise stick to flip()

if __name__ == "__main__": #if file is not a module
    button1 = Button([130, 200, 90, 100], text="Press")
    button2 = Button([280, 200, 90, 100], text="Me", default_colour=(255,255,0))

    buttons = [ #array of dicts to store buttons and callback functions, for multiple buttons
        {
         "button": button1,
         "func": response1
        },
        {
         "button": button2,
         "func": response2
        }
    ]

    main(buttons)