NOTES: Im new in react native and i see there are so many approaches and with this error i thought the developer who built this app build it differently from what i learn so i don't understand why he didn't put the android folder
so i just joined a project and im going to run the apps in my pc by cloning it from github but when i try to npx react-native run-android it failed to run and the log is like this
error Android project not found. Are you sure this is a React Native project?
If your Android files are located in a non-standard location (e.g. not inside 'android' folder),
consider setting project.android.sourceDir option to point to a new location.
info Run CLI with --verbose flag for more details.
the folder structure is like this
The files show that the project is created with Expo. Specifically, you have a managed expo project.
npx react-native run-android would compile an android app from source, with Expo's managed workflow that's not needed. You will need the Expo Go App.
Expo also comes with its own commands to start the bundler. Instead of running npx react-native ... make use of the expo-cli running: npx expo start
However, in the package.json there is very likely a script called start. In that case, it's easier for you to run npm start.
After running this command the expo console opens. Here you can press a to open the app using expo go (or instructions on how to do so).
Alternatively, you can run npx expo run:android to start the expo go app on android yourself.
you are using an expo, there is a folder named .expo-shared, after
npm install
Try to run
npm start
or
expo start
or
npx expo start
something like this will appear:
https://imgur.com/U9I7Gf4
after that go to the terminal, open the emulator in you computer and click on the terminal and press 'a',
Code example I am trying to run: https://github.com/nshaposhnik/react-native-maps-example
I am on windows 10.
What I do:
Downloaded the code
Extracted to folder
Setup with the following after deleting yarn.lock:
yarn add react-native-maps
yarn add react-native-maps-directions
yarn add react-native-google-places-autocomplete
npm install
npm audit fix
Edit the code in the 3 places that requires my custom google API key which I got from the developer site
Tried running via:
npm start
I get a successful run in the terminal (" Welcome to React Native! Learn once, write anywhere"), but no browser opens up. I go to localhost:8081 in my browser and see a barren webpage with the following text:
React Native packager is running.
Visit documentation
That's all. Nothing in the sample project runs. I just want to run their app in a browser or emulator, though I don't have any of the phone emulators working, so I just want to run in web browser.
How can I make this work from the above example? Much appreciated.
You have to run emulator separately on "Windows" using android studio or command line, and after open your project using VsCode(or your editor) and the run following command ,
react-native run-android
Your app will run on your opened emulator
In packager I am getting the following error when I am running the command
react-native run-android
The packager output is:
Loading dependency graph...
Bundling `index.js` [development, non-minified] ░░░░░░░░░░░░░░░░ 0.0% (0/1)Error: watch
ENOSPC
at _errnoException (util.js:1019:11)
at FSWatcher.start (fs.js:1383:19)
at Object.fs.watch (fs.js:1409:11)
at NodeWatcher.watchdir
Any help? thanks in advance.
Try to re run the project and clean the project, cd android and then gradlew clean, and I suggest to run react-native start first, then open a new terminal and run react-native run-android, also i found the troubleshooting case which is quite similar, https://facebook.github.io/react-native/docs/troubleshooting.html#unable-to-start-react-native-package-manager-on-linux hope that helps:)
I followed the steps:
Kill my node server process which is started on 8081 port.
Restarted my complete development environment
And then started my packager(react-native start) as super user.
then executed react-native run-android.
And it is running successfully now.
I am following the tutorial on the official React Native website.
Using the following to build my project:
react-native run-ios
I get the error:
Found Xcode project TestProject.xcodeproj
xcrun: error: unable to find utility "instruments", not a developer
tool or in PATH
Command failed: xcrun instruments -s
xcrun: error: unable to find utility "instruments", not a developer
tool or in PATH
Although, when I run the app from the .xcodeproj, everything works fine.
Any suggestions?
Check out this link (Running react-native run-ios occurs an error?). It appears to be a problem with the location of Command line tools.
In Xcode, select Xcode menu, then Preferences, then Locations tab. Select your Xcode version from the dropdown and exit Xcode.
You may need to install or set the location of the Xcode Command Line Tools.
Via command line
If you have Xcode downloaded you can run the following to set the path:
sudo xcode-select -s /Applications/Xcode.app
If the command line tools haven't been installed yet, you may need to run this first:
xcode-select --install
You may need to accept the Xcode license before installing command line tools:
sudo xcodebuild -license accept
Via Xcode
Or adjust the Command Line Tools setting via Xcode (Xcode > Preferences > Locations):
An update for anybody (like me) who's run into this in Xcode 13 -- the instruments command has been removed.
Updating to the latest version of react-native in your package.json file will no longer try to use the instruments command.
By default, after installing Xcode command-line not selected, so open Xcode and go to Preferences >> Locations and set Command Line Tools...
This worked for me in MAC High Sierra, Xcode Version 9.3:
Press i to open iOS emulator...
And You can see a cool new iPhone simulator like below image:
In my case the problem was that Xcode was not installed.
I had to accept the XCode license after my first install before I could run it. You can run the following to get the license prompt via command line. You have to type agree and confirm as well.
sudo xcodebuild -license
Problem is your Xcode version is not set on Command Line Tools, to solve this problem open Xcode>Menu>preferences> location> here for Command Line tools select your Xcode version, that's it.
For those like me who come to this page with this problem after updating Xcode but don't have an issue with the location setting, restarting my computer did the trick.
For me, it turns out that there was an iOS system update pending asking to restart the computer. Restart and let the update finish solved my problem.
In my case the SDKROOT environment variable was wrong, which referred to an old version of iPhoneOSxx.x.sdk. (Perhaps this would have automatically resolved itself after a reboot?)
You can check by running echo $SDKROOT and verifying that it's a valid path.
I fixed it by updating in .bash_profile:
export SDKROOT=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS11.2.sdk
None of these solutions worked for me. These two similar problems offer temporary solutions that worked, it seems the simulator process isn't being shutdown correctly:
Killing Simulator Processes
From https://stackoverflow.com/a/52533391/11279823
Quit the simulator & Xcode.
Opened Activity monitor, selected cpu option and search for sim, killing all the process shown as result.
Then fired up the terminal and run sudo xcrun simctl erase all. It will delete all content of all simulators. By content if you logged in somewhere password will be gone, all developer apps installed in that simulator will be gone.
Opening Simulator before starting the package
From https://stackoverflow.com/a/55374768/11279823
open -a Simulator; npm start
Hopefully a permanent solution is found.
Go to Xcode Preferences
Locate the location tab
Set the Xcode version in Given Command Line Tools
Now, it ll successfully work.
If the previous answers didn't help you, you're probably dealing with an outdated react-native version. If you want to run your app on device without upgrading React-Native, you'll have to run the app directly from Xcode instead of doing it in the CLI. So open the <appname>.xcworkspace, select your device on the right-hand dropdown and press the "Run" icon.
Xcode screenshot
In Mac: After all, you are getting this issue, there may be a chance of missing the following in System Preferences -> Network -> Ethernet -> Select Advanced -> Proxies
add the following line,
*.local,localhost
This is how I got the solution,
> rm -rf ~/Library/Developer/Xcode/DerivedData
> sudo rm -rf /Library/Developer/CommandLineTools
> xcode-select --install
> sudo xcodebuild -license accept
Xcode > Preferences > Location > Command Line Tools choose.
simply go to Xcode
click on Xcode from the top left menu
Xcode->preferences-> location-> click comman line option and set Xcode version.
For any such problem:
Go to .expo folder
Find apk-cache
Remove that folder
and you are done..
Hope it helps?
I have hitting my head on this for past 3 hours.
What i call: ../../latest-cli/nativescript-cli/bin/tns run android --watch --device=emulator-5554
Some ideas would be awesome!
Make sure you have all of the latest parts of NativeScript (core modules, runtime, and CLI). There's a great blog post here: http://fluentreports.com/blog/?p=323 which outlines that all of the above need to be in sync. Then you should try running tns platform remove android then tns platform add android. Then make sure you uninstall this failed build, and install a fresh build after adding the platform back.
Also just open the emulator and call tns livesync android --watch and the CLI will detect the running emulator. No need to specify.