Issue 152 fix example program.
Issue 152 fix example program.

oktayacikalin/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,oktayacikalin/pyglet,theblacklion/pyglet,mammadori/pyglet,theblacklion/pyglet,mammadori/pyglet,theblacklion/pyglet,oktayacikalin/pyglet,theblacklion/pyglet,mammadori/pyglet,mammadori/pyglet,theblacklion/pyglet