description

# deltaX property Null safety

num deltaX

The amount that is expected to scroll horizontally, in units determined by deltaMode.

See also:

- WheelEvent.deltaX from the W3C.

## Implementation

    num get deltaX {
      // deltaX may be missing or undefined.
      num? value = JS('', '#.deltaX', this);
      if (value != null) return value;
      throw new UnsupportedError('deltaX is not supported');
    }