H a n d s o n, p r o j e c t b a s e d

Deactivating the Play Button
One issue with our Play button is that the button region on the screen will 
continue to respond to clicks even when the Play button isn’t visible. If you 
click the Play button area by accident after a game begins, the game will 
restart! 
To fix this, set the game to start only when 
game_active
is 
False
:
def _check_play_button(self, mouse_pos):
"""Start a new game when the player clicks Play."""
u
button_clicked = self.play_button.rect.collidepoint(mouse_pos)
v
if button_clicked and not self.stats.game_active:
# Reset the game statistics.
self.stats.reset_stats()
--snip--
The flag 
button_clicked
stores a 
True
or 
False
value u, and the game 
will restart only if Play is clicked and the game is not currently active v. 
To test this behavior, start a new game and repeatedly click where the Play 
button should be. If everything works as expected, clicking the Play button 
area should have no effect on the gameplay.
Hiding the Mouse Cursor
We want the mouse cursor to be visible to begin play, but once play begins, it 
just gets in the way. To fix this, we’ll make it invisible when the game becomes 
active. We can do this at the end of the 
if
block in 
_check_play_button()
:
def _check_play_button(self, mouse_pos):
"""Start a new game when the player clicks Play."""
button_clicked = self.play_button.rect.collidepoint(mouse_pos)
if button_clicked and not self.stats.game_active:
--snip--
# Hide the mouse cursor.
pygame.mouse.set_visible(False)
alien_invasion.py
alien_invasion.py

---

Scoring
285
Passing 
False
to 
set_visible()
tells Pygame to hide the cursor when the 
mouse is over the game window.
We’ll make the cursor reappear once the game ends so the player can 
click Play again to begin a new game. Here’s the code to do that:
def _ship_hit(self):
"""Respond to ship being hit by alien."""
if self.stats.ships_left > 0:
--snip--
else:
self.stats.game_active = False
pygame.mouse.set_visible(True)
We make the cursor visible again as soon as the game becomes inactive, 
which happens in 
_ship_hit()
. Attention to details like this makes your game 
more professional looking and allows the player to focus on playing rather 
than figuring out the user interface.