button.py

import pygame.font

class Button():

    def __init__(self,ai_settings,screen,msg):
        """Initialize button attributes"""
        self.screen=screen
        self.screen_rect=screen.get_rect()

        #set the dimensions and properties of the button.
        self.width,self.height=200,50
        self.button_color=(0,255,0)
        self.text_color=(255,255,255)
        self.font=pygame.font.SysFont(None,48)

        #Build the button's rect object and center it.
        self.rect=pygame.Rect(0,0,self.width,self.height)
        self.rect.center=self.screen_rect.center

        #The button message needs to be prepped only once.
        self.prep_msg(msg)

    def prep_msg(self,msg):
        """Turn msg into a rendered image and center text on the button."""
        self.msg_image=self.font.render(msg,True,self.text_color,self.button_color)
        self.msg_image_rect=self.msg_image.get_rect()
        self.msg_image_rect.center=self.rect.center

    def draw_button(self):
        #Draw blank button and then draw message.
        self.screen.fill(self.button_color,self.rect)
        self.screen.blit(self.msg_image,self.msg_image_rect)