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