create-react-native-app install & using

create-react-native-app  install & using

1. node install (설치)

2. npm install -g create-react-native-app

3. create-react-native-app my-project

4. cd my-project

5. npm start

6. install Expo on device to test 테스트할 장치에  Expo 어플 설치

7. execute Expo app & scan my-project QR-code

Happy Hacking !!!

-->> React-Native Lesson

create-react-native-app error

android navigator.geolocation.getCurrentPosition(succes, error, options)..

    componentDidMount() {

        var options = {

          enableHighAccuracy: true,

          timeout: 5000,

          maximumAge: 0

        };

        function success(pos) {

          var crd = pos.coords;

          console.log(pos);

          console.log('Your current position is:');

          console.log('Latitude : ' + crd.latitude);

          console.log('Longitude: ' + crd.longitude);

          console.log('More or less ' + crd.accuracy + ' meters.');

        };

        function error(err) {

          console.warn('ERROR(' + err.code + '): ' + err.message);

        };

        navigator.geolocation.getCurrentPosition(success, error, options);

    }

ERROR<E_LOCATION_DISABLED>........     

enable using location on your device  장치의 위치정보 확인을 사용 가능하게한다.

The reason why React Native HMR doesn't work with stateless functional components is because it uses react-transform-hmr which doesn't support them (it says so in the README).

React Native will either have to use something like react-hot-loader (which I'm not sure it can since it doesn't use Webpack but could still implement some of its features in the packager) or roll up their own solution that works for stateless functional components.

How to Roll up :) 

Device >>settings>>general >>applications>>Expo >> Delete data ( Not a delete application) >>

rerun your react-native project

Module HMRClient is not a registered callable module (calling enable)

try restarting your packager or computer to see if that helps. Also ensure that your package.json and app.json are pointing to the same sdk

packager 또는 컴퓨터를 다시 시작하여 도움이되는지 확인하십시오. 또한 package.json과 app.json이 동일한 sdk를 가리키고 있는지 확인하십시오.

Error: google chrome exited with error error spawn cmd enoent

1. Close Expo app of device and react-native project
2. Device >>settings>>general >>applications>>Expo >> Delete data ( Not a delete application) 
3. Open Chrome browser and move localhost:19001/debugger-ui  and F12(  Don't hide windows  state separate window to see)
4. Run react-native project on computer and Expo app
5. Run your react-native application in Expo app on your device
6. Shake a device or  use menu
7. Tohch Debug JS Remotely

Uncaught Error: 23.0.0 is not a valid sdk version.

Options are 15.0.0 ........  UNVERSIONED  Fatal Error

Try updating the Expo app on your phone through the Play Store.