onError method
Called when an exception was occurred during the request.
Implementation
@override
void onError(DioException err, ErrorInterceptorHandler handler) {
var options = err.requestOptions;
dynamic bind = options.extra[dioExtraBind];
if (options.cancelToken != null) {
CancelTokenPool().remove(bind, options.cancelToken!);
}
if (err.type == DioExceptionType.cancel) return;
super.onError(err, handler);
}