Examples: Fix incorrect usage of close() in some examples (#2545)

Author: einarf

arcade/examples/astar_pathfinding.py

@@ -215,7 +215,7 @@ def on_key_press(self, key, modifiers):
             self.right_pressed = True
         # Close the window / exit game
         elif key == arcade.key.ESCAPE:
-            self.close()
+            self.window.close()
 
     def on_key_release(self, key, modifiers):
         """Called when the user releases a key. """

arcade/examples/asteroid_smasher.py

@@ -316,7 +316,7 @@ def on_key_press(self, symbol, modifiers):
             self.start_new_game()
         # Quit if the player hits escape
         elif symbol == arcade.key.ESCAPE:
-            self.close()
+            self.window.close()
 
     def on_key_release(self, symbol, modifiers):
         """ Called whenever a key is released. """

arcade/examples/dual_stick_shooter.py

@@ -279,7 +279,7 @@ def on_key_press(self, key, modifiers):
             self.player.start_pressed = True
         # close the window if the user hits the escape key
         elif key == arcade.key.ESCAPE:
-            self.close()
+            self.window.close()
 
         rad = math.atan2(self.player.change_y, self.player.change_x)
         self.player.angle = math.degrees(rad) + ROTATE_OFFSET

arcade/examples/particle_fireworks.py

@@ -369,7 +369,7 @@ def on_draw(self):
 
     def on_key_press(self, key, modifiers):
         if key == arcade.key.ESCAPE:
-            arcade.close_window()
+            self.window.close()
 
 
 def firework_spark_mutator(particle: FadeParticle):

arcade/examples/slime_invaders.py

@@ -200,7 +200,7 @@ def on_draw(self):
 
     def on_key_press(self, key, modifiers):
         if key == arcade.key.ESCAPE:
-            self.close()
+            self.window.close()
 
     def on_mouse_motion(self, x, y, dx, dy):
         """