如何指向本地主机: 8000与 Dart http 软件包在扑动?

我遵循 颤动网络/HTTP 教程对在本地主机: 8000上运行的服务器执行 GET 请求。通过浏览器访问我的本地主机工作正常。我的代码是这样的:

var url = 'http://localhost:8000';
Future<String> getUnits(String category) async {
var response = await httpClient.get('$url/$category');
return response.body;
}

当我指向任何实际的 URL (比如 https://example.com)时,这种方法都可以很好地工作,但是当我指向 https://localhost:8000https://localhost(或这些 URL 的任何变体)时,我会得到一个错误,从以下开始:

E/flutter ( 4879): [ERROR:topaz/lib/tonic/logging/dart_error.cc(16)] Unhandled exception:
E/flutter ( 4879): SocketException: OS Error: Connection refused, errno = 111, address = localhost, port = 47060
E/flutter ( 4879): #0      IOClient.send (package:http/src/io_client.dart:30:23)

上面错误中的端口每次重新加载应用程序时都会发生变化。我查看了 http package code,似乎没有指定 URL 端口的方法。如何指向本地主机?

104093 次浏览

Short answer: You can pass an Uri instead of a string as parameter

      var client = createHttpClient();
client.get(new Uri.http("locahost:8000", "/category"));

Replacing the string localhost with 10.0.2.2 resolved it for me, since I was running the code in the Android emulator, which is running in a VM. It's essentially a duplicate of this question.

replace 'localhost' in your url to wifi connection ip e.g : 'http://localhost:8000' => 'http://192.168.1.102:8000'. you can get your wifi ip from command prompt with cmd>ipconfig (wireless LAN adapter WI-FI.

var url = 'http://192.168.1.102:8000';
Future<String> getUnits(String category) async {
var response = await httpClient.get('$url/$category');
return response.body;
}

Localhost via the computer browser I assume?

Using "http://localhost:port" in the Flutter code points to the local emulator device and not the local server running on your coomputer.

Point url to the IP Address of your server machine instead, that should solve the issue.

to find ip is ifconfig mac / linux

en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500




this one => inet 192.168.43.57 netmask 0xffffff00 broadcast 192.168.43.255


nd6 options=201<PERFORMNUD,DAD>
media: autoselect
status: active

start php

php -S 192.168.43.57:5000 index.php

than declare on future

Future<String> getIsi()async{
final res = await new Dio().get('http://192.168.43.57:5000/lihat-isi');
print('res.data');
return res.data;
}

an result is

I/flutter ( 3250): [{"id":"1","judul":"asasa","gambar":"asa","ket":"asa"},{"id":"2","judul":"asasa","gambar":"asa","ket":"asa"},{"id":"3","judul":"asasa","gambar":"asa","ket":"asa"},{"id":"4","judul":"asasa","gambar":"asa","ket":"asa"}]

Try forwarding the port of your emulator or the device to your computers port

e.g if your server is running on localhost:8000 then run this command

adb reverse tcp:8000 tcp:8000

this command actually redirects your phone’s port 8000 to your computer’s port 8000.And now your client should be able to talk to the server running locally

Tip: this also works if you want to run your flutter web app on your phone locally using

flutter run -d web-server

more details here

If you are using an Android emulator then localhost on the emulator is not 127.0.0.0 it is 10.0.2.2, so, on Android emulator you need to write https://10.0.2.2:8000, the https://127.0.0.1:8000 will not work on real device too. because localhost means something different on real device.

For more information on how to connect a Flutter app to localhost on emulator or on a real device click on the link Connecting Flutter application to Localhost

If you are trying to access localhost api through emulator, Change localhost to your IPV4 Address. And if you are running your api in Visual Studio set the app URL also to be IPV4 address. In my case I changed it from "localhost:5001" to 192.168.XX.XX:5001

if you don't change the backend it will return “Bad Request-Invalid Hostname” When accessing localhost from emulators

enter image description here

im using ubuntu 20LTS, laravel backend, flutter http package.

  • Step 1: in terminal run sudo apt-get install net-tools . this package supports ifconfig command to work.
  • Step 2: in terminal run ifconfig . then in the output search this line inet 192.168.43.217 netmask 255.255.255.0 broadcast 192.168.43.255 . then copy the inet 192.168.43.217 ip-address. also, note that ip-address will be different for you. for me it is 192.168.43.217 .
  • Step 3: goto your laravel project cd your_laravel_project and then run sudo php -S 192.168.43.217:81 -t public to serve to inet address.
  • Step 4: then from flutter static const _apiRoute = "http://192.168.43.217:81/api/login". huh!! this worked for me.

I had the same problem, so apparently, I found a solution for this problem, so because you are in a virtual environment with your phone you cant use the localhost because the phone is not connected with your PC so simply, in my case, it worked, just use:

10.0.2.2:PORT

use this URL with your Port and it should work :)

if it is still not working even after pointing to 10.0.:2.2:port Most likely Android is not allowing the http traffic.

change the AndroidManifest.xml android/app/src/main

include

 android:usesCleartextTraffic="true"

as shown below

<application
android:name="io.flutter.app.FlutterApplication"
android:label="app_name"
android:icon="@mipmvvap/ic_vvlauncher"
android:usesCleartextTraffic="true">

If your backend is on LARAVEL, make sure to serve the domain to your IP address and port before using it on your flutter application

To serve do this

php artisan serve --host=192.168.1.100 --port=8000

That should solve the problem.

https://ngrok.com/download

Download ngrokand run ngrok http <your localhost URL> (Please run this command in same location where you are download ngrok.exe) EX ngrok http http://127.0.0.1:8000

After that you will get URL forwarder link like http://98b9-2402-4000-2380-c5a6-c5c9-86cf-ea4d-66af.ngrok.io and change your base URL to this.

That's it! Enjoy and happy coding!!