Width not change on orientation change

[ZionChang]

When I rotate my iPad, the width of Swiper doesn't change.
According to doc which says that width: If no specify default enable fullscreen mode by flex: 1.
But I don't think it works when I rotate the divide.

So is this a bug or something I missed?

version
"react": "16.0.0-alpha.6"
"react-native": "0.44.2"
"react-native-swiper": "^1.5.4"