我已经坚持了很长时间了。我有一门纽扣课。您已经可以选择按钮，单击按钮，然后释放按钮（这会导致事件发生）。我想在你松开按钮时发出声音，但我就是做不到。我不明白你该怎么做，我什么都试过了。换句话说，我想确保鼠标在选择按钮时被按住，如果它在那个位置释放，一个名为 release 将在一帧内切换为true。然后我可以检查释放是否是真的，然后我会播放声音。我的问题是：我需要检查什么条件才能得到这个结果 release 一帧的属性切换为true？这是我的代码结构：

# "mouse_down" is a global for when the mouse is being held down

# "clicked" is a global variable for the first frame at which the mouse is held down

# I also have a "release" global variable for the frame that the mouse stops clicking, this variable isn't currently being used.

class Button:
    def __init__(self, pos, size, font, text, colors):
        """
        colors[n]

        0: fill   unselected
        1: border unselected
        2: text   unselected
        3: fill   selected
        4: border selected
        5: text   selected
        6: fill   clicked
        7: border clicked
        8: text 
        """

        self.pos = pos
        self.size = size
        self.font = font
        self.text = text
        self.colors = colors
        self.selected = False
        self.clicked = False
        self.release= False

    def update(self):
        # If the mouse is hovering on the button
        if (pygame.mouse.get_pos()[0] > button.pos[0] and pygame.mouse.get_pos()[0] < button.pos[0] + button.size[0]) and (pygame.mouse.get_pos()[1] > button.pos[1] and pygame.mouse.get_pos()[1] < button.pos[1] + button.size[1]):
            self.selected = True

            if clicked: 
                self.clicked = True

            if not mouse_down:
                self.clicked = False

        else:
            self.selected = False
            self.clicked = False

现在我们来澄清一下，假设我用鼠标按住click按钮，将它拖到按钮的位置，然后放开，release属性不应该打开，因为首先需要将鼠标放在按钮上。