import 'dart:convert'; import 'package:dio/dio.dart'; import 'package:flutter/foundation.dart'; BaseOptions dioOptions = BaseOptions(baseUrl: 'http://localhost:8080'); Future shortenUrl(String url) async { try { assert(url.isNotEmpty); final Response res = await Dio(dioOptions).post('/', data: {'url': url}); final Map json = jsonDecode(res.data ?? '') as Map; print(json); return json['url'] as String?; } catch (err, st) { if (kDebugMode) { print('Encountered an error:'); print(st); print(err); } return null; } }