Pygame - 使用文字作為按鈕

按鈕是典型遊戲視窗中重要的元素。我們可以使用文字或影像表面物件作為按鈕，這樣當它被點選時可以觸發某個動作。

讓我們嘗試顯示帶文字標題的三個按鈕。

text1=font.render(" START ", True, white)
text2=font.render(" PLAY ", True, white)
text3=font.render(" STOP ", True, white)

要圍繞這些按鈕繪製邊框，請獲取其 Rect 物件。

rect1 = text1.get_rect(topleft=(10,10))
rect2 = text2.get_rect(topleft= (100,10))
rect3 = text3.get_rect(topleft= (200,10))

在事件迴圈內，用紅色邊框貼上文字按鈕。

screen.blit(text1, rect1)
pygame.draw.rect(screen, (255,0,0),rect1,2)
screen.blit(text2, rect2)
pygame.draw.rect(screen, (255,0,0),rect2,2)
pygame.draw.rect(screen, (255,0,0),rect3,2)
screen.blit(text3, rect3)

使用 Rect 物件的 collidepoint() 函式來識別哪個按鈕已被點選。

if event.type == pygame.MOUSEBUTTONDOWN:
   if rect1.collidepoint(event.pos):
      msg = "START Button was pressed"
   if rect2.collidepoint(event.pos):
      msg = "PLAY Button was pressed"
   if rect3.collidepoint(event.pos):
      msg = "STOP Button was pressed"

將適當的訊息顯示為文字表面 −

img=font.render(msg, True, (0,0,255))
imgrect=img.get_rect()
imgrect.center = (200 , 150 )
pygame.draw.rect(screen, bg, imgrect)
screen.blit(img, imgrect)

示例

以下是完整的程式碼 −

import pygame

pygame.init()
screen = pygame.display.set_mode((400, 300))
done = False

font = pygame.font.SysFont("Arial", 14)
text1=font.render(" START ", True, white)
text2=font.render(" PLAY ", True, white)
text3=font.render(" STOP ", True, white)

rect1 = text1.get_rect(topleft=(10,10))
rect2 = text2.get_rect(topleft= (100,10))
rect3 = text3.get_rect(topleft= (200,10))
bg = (127,127,127)
msg=" "
screen = pygame.display.set_mode((400,300))
screen.fill(bg)
while not done:
   for event in pygame.event.get():
      screen.blit(text1, rect1)
      pygame.draw.rect(screen, (255,0,0),rect1,2)
      screen.blit(text2, rect2)
      pygame.draw.rect(screen, (255,0,0),rect2,2)
      pygame.draw.rect(screen, (255,0,0),rect3,2)
      screen.blit(text3, rect3)
      
      if event.type == pygame.QUIT:
         done = True
      if event.type == pygame.MOUSEBUTTONDOWN:
         if rect1.collidepoint(event.pos):
            msg = "START Button was pressed"
         if rect2.collidepoint(event.pos):
            msg = "PLAY Button was pressed"
         if rect3.collidepoint(event.pos):
            msg = "STOP Button was pressed"
      img=font.render(msg, True, (0,0,255))
      imgrect=img.get_rect()
      imgrect.center = (200 , 150 )
      pygame.draw.rect(screen, bg, imgrect)
      screen.blit(img, imgrect)

   pygame.display.update()

輸出

當每個按鈕被點選時，顯示視窗將顯示下面的輸出 −