deltaY property
The amount that is expected to scroll vertically, in units determined by deltaMode.
See also:
- WheelEvent.deltaY from the W3C.
Implementation
num get deltaY {
// deltaY may be missing or undefined.
num? value = JS('', '#.deltaY', this);
if (value != null) return value;
throw new UnsupportedError('deltaY is not supported');
}