dynamicItemOpacity sometimes does not work on Android device

[suhirotaka]

Hello,

I really like your plugin, thank you!

I found dynamicItemOpacity sometimes does not work on Android device.
After some digging, I found difference in calculateOpacity is very small non-zero value (1.8189894035458565e-12) in case of dynamicItemOpacity not working, whereas difference is zero in normal case.

scroll_snap_list/lib/scroll_snap_list.dart

Lines 216 to 222 in 69d37c3

	double calculateOpacity(int index) {
	//scroll-pixel position for index to be at the center of ScrollSnapList
	double intendedPixel = index * widget.itemSize;
	double difference = intendedPixel - currentPixel;
	return (difference == 0) ? 1.0 : widget.dynamicItemOpacity ?? 1.0;
	}

Here are screenshot videos which show different opacity behavior of the last item.

OK:

2021-08-19.16.43.01.mov

not OK:

2021-08-19.16.44.31.mov