I am using expo-cli#3.0.10
This app works fine in client expo which installed in device
Ok I believe I found the core problem - DNS issue.
Your Android simulator cannot properly resolve the hostname using your current DNS for whichever OS you are on be it Mac OS, Windows or Linux.
Follow this link to set your DNS address to 8.8.8.8 or some other applicable DNS.
Once you set your DNS properly it should work.
Make sure that 8.8.8.8 is the first DNS address in the list(?) of DNS addresses so that your system will resolve hostnames using the Google DNS first.
Reposting the useful information from that link below,
Change the DNS address of your network to 8.8.8.8:
MacOSX:
Open "System Preferences"
Click on "Network"
Select the network which your computer is connected and click on "Advanced"
Select "DNS", Select the "+" button, type "8.8.8.8"
Select "Ok" and "Apply"
Windows & Linux:
https://developers.google.com/speed/public-dns/docs/using
After that close the emulator and start it again.
This case happened to me whenever I switch from a network to another without restarting my emulator.
The simplest way to solve this was to restart my emulator.
I hope it helps,
For my case, this error occurred because I changed from LAN to Wireless Internet connection while the project is building.
Solution: Close the Emulator and restart Android Studio. Run the project (either npm start or expo start) and this worked for me.
You need to start expo server first. Use expo start. Then run your project.
After starting your expo server re-start your project.
When trying to run exp start --tunnel in a react-native project, I often see the warning:
22:15:31 [exp] Your URL is: exp://192.168.200.83:19000
....
22:15:31 [exp] Switched to a LAN URL because the tunnel appears to be down. Only devices in the same network can access the app. Restart with exp start --tunnel to try reconnecting.
This is a problem since none of my devices or the AVD can connect to this URL to download the project.
The problem does not seem to related to any firewall settings as it does not occur every time (just very consistently). When the error does not happen, I get a URL that I can work with that looks like:
22:44:38 [exp] Your URL is: exp://en-ux3.myexpousername.myapp.exp.direct:80
Is there something that can be done about this to get it to stop switching? What causes this switching exactly? Is there some way to get devices to be able to use this URL instead (I have an android device connected to same wifi, but seems to be unable to download the project from the LAN URL)?
** Totally new to react-native and expo, so if I am missing evidence of any common debugging steps for this kind of problem, please let me know what they may be in the comments so I can update the question.
UPDATE:
A similar question to this is addressed in the expo forums: https://forums.expo.io/t/switched-to-a-lan-url-because-the-tunnel-appears-to-be-down-only-devices-in-the-same-network-can-access-the-app-you-can-restart-the-project-to-try-reconnecting/4483.
I was having the message
Switched to a LAN URL because the tunnel appears to be down. Only devices in the same network can access the app. You can restart the project to try reconnecting.
And I've solved it closing Visual Studio (then pressing the Restart button from Expo XDE)
I created my project in react native by CLI:
_npm install -g create-react-native-app
_create-react-native-app AwesomeProject
_cd AwesomeProject
_npm start
Then I installed expo in my Android phone, and scanned a QR code on my computer screen.
However, my phone can't connect to project, and I don't know why. It just loads and fails. This is error message:
Could not load exp:// 192.168.56.1:19000. Network response timed out.
This is view error:
"Uncaught Error: java,not.SocketTimeoutException: faild to connect to/192.168.56.1 (port 19000) after 10000 ms.
I'm trying to fix it, but still can't get it working. My phone and my laptop are on the same network. What can I do now?
I had the same problem but solved by running expo start --tunnel
Select LOCAL instead of LAN.
I kicked myself when I fixed this.
I had the same issue, turns out my firewall was blocking my connection to the development server port (for me it was 19000). Solved it by disabling firewall.
Choose Tunnel Instead of LAN or Local in connection tab. This solved the issue for me.
Keep a look on this issue for the answer:
https://github.com/react-community/create-react-native-app/issues/60
Make sure that your device and computer are one same LAN/Wifi. It will work.
Also use LAN option.
check open port using
ufw status verbose
And if you don't see the port You are working on
for example 19000 => expo
try this
ufw allow 19000
I've had a similar problem on iOS - the project showed up in the Expo app but didn't want to connect.
Here's what I did:
Connect your PC to your device through USB cable
Download the newest xde from: https://github.com/expo/xde/releases
Install XDE, create a new project from the gui (do NOT use your old project from create-react-app, as it may also show up in XDE) and click the newly created (in XDE) project under "My Projects".
Now your project should show up in the Expo app on your phone. If it doesn't try sending yourself the link to your app over email (to your own inbox, and open the link on your phone), mine looks like this: exp://5c-gp9.[accountname].my-new-project.exp.direct:80
I had this problem when my phone was connected via wifi and my destop was connected via LAN. I changed the connection mode in the browser window to tunnel, reloaded the expo app and was able to connect to my application. This was on my iOS device.
I got this issue on Win 10 with android and solved by the adding a firewall rule for my device (device IP as remote). I was using ESET NOD antivirus and it was block the device from accessing node.exe
for local testing e.g comnputer , simulator
expo start
for Real mobile device
expo start --tunnel
I'm on windows 10.
My network was set to public, but it needed to be private - so that it could safely expose devices like printers and in this case the Expo connection.
I went in my Wifi setting and clicked on Private:
If you are using windows 10 do the following. It worked for me
1. Check if your phone and pc are sharing the same router/hotspot/wifi connection. better still you can connect your pc to your phone hotspot.
2. Configure the network you are using as private. you can do so using this link https://www.digitalcitizen.life/how-set-your-networks-location-private-or-public-windows-10/
3. Off your windows defender and any other antivirus. The windows and other antivirus defender acts as a firewall and prevents expo client from working.
It will work I assure you
I was having the same issue, the solution is easy just make a Firewall rule that allows connection from your mobile device to your PC. open port number 19000 and in the IP put your phone IP address then allow the connection TCP/UDP in both directions, and everything will be OK.
Usually, you can edit the Firewall rules through your antivirus installed on your PC.
Careful don't disable your firewall, it will hurt you a lot.
This problem is due to the sdk version of the project is not compatible with the expo go ,so go to app.json of your project and edit to the latest version of sdk
hai every one i am trying to run the react-native android app in device then it throws an error like as mentioned below
can any one please give me suggestions for how to solve this error,Any help much appreciated
Try following the steps on the guide page.
You may have to set the address of your dev server.
Configure your app to connect to the local dev server via Wi-Fi
Make sure your laptop and your phone are on the same Wi-Fi network.
Open your React Native app on your device. You can do this the same way you'd open any other app.
You'll see a red screen with an error. This is OK. The following steps will fix that.
Open the Developer menu by shaking the device or running adb shell input keyevent 82 from the command line.
Go to Dev Settings.
Go to Debug server host for device.
Type in your machine's IP address and the port of the local dev server (e.g. 10.0.1.1:8081). On Mac, you can find the IP address in System Preferences / Network. On Windows, open the command prompt and type ipconfig to find your machine's IP address (more info).
Go back to the Developer menu and select Reload JS.
I am getting the following message on accessing internet from native blackberry simulator.
"Unable to connect to the internet please try again later. If the problemt persists please contact your service provide."
Getting this issue on blackberry standalone simulator for 9860. I have not installed JDE or any other Dev tool. Seen lots of comments asking for adding the proxy details on HTTP HEADER, but it didnt work for me. I am trying in corporate network having proxy
Please help
Did you try to install and run the BlackBerry MDS? https://swdownloads.blackberry.com/Downloads/entry.do?code=F9BE311E65D81A9AD8150A60844BB94C
You have to run it BEFORE running the simulator to be able to use the internet connection.
Have you tried this on your simulator:
1) Go to "Manage Connections"
2) Click "Set Up Wi-Fi Network"
3) Either click "Default WLAN Network" if you see it there or create it using "Manually Connect to Network"
Hope this helps.