public static By callback(final Function<SearchContext, List<WebElement>> callback) {
		if (callback == null)
			throw new IllegalArgumentException("Cannot find elements when the callback is null");

		return new ByCallback(callback);
	}
public static By callback ( final Function < SearchContext , List < WebElement > > callback ) { if ( callback == null ) throw new IllegalArgumentException ( "Cannot find elements when the callback is null" ) ; return new ByCallback ( callback ) ; }
Finds elements via custom callback which accepts {@link SearchContext}
and returns {@link List} of {@link WebElement}s.

@param callback callback
@return a By which locates elements by callback.