Why Changes are not reflecting in React native?

Question

I am changing something in .js file for ex. any text for textfiled placeholder. But after running command react-native run-android nothing is changing in android emulator. only when i run npm run bundle-android and then run react-native run-android changes are reflecting.

My package.json is like

{
  "name": "xyz",
  "version": "0.0.1",
  "private": true,
  "scripts": {

    "start": "react-native start",
    "bundle-android": "react-native bundle --entry-file index.js --platform android --dev false --bundle-output ./android/app/src/main/assets/index.android.bundle --assets-dest ./android/app/src/main/res/",
    "bundle-ios": "react-native bundle --entry-file index.js --bundle-output ./ios/bundle/index.ios.jsbundle --platform ios --assets-dest ./ios/bundle --dev false",
    "test": "jest",
    "ios": "react-native run-ios --simulator 'iPhone X'",
    "android": "react-native run-android -- --reset-cache",
    "android-ete": "ENVFILE=.env.ete react-native run-android -- --reset-cache",
    "ios-ete": "ENVFILE=.env.ete react-native run-ios",
    "ios-prod": "ENVFILE=.env.prod react-native run-ios",
    "exportcert-ete": "java -jar BKSPubKeyTool.jar --importkeystore keystore_ete.bks --alias oauth.testing --password keystorepwd --exportcert src/keystore/id_rsa_ete.pem --exportjs src/keystore/pubKey_ete.js",
    "exportcert-prod": "java -jar BKSPubKeyTool.jar --importkeystore keystore.bks --alias oauth --password keystorepwd --exportcert src/keystore/id_rsa_prod.pem --exportjs src/keystore/pubKey_prod.js",
    "lint": "eslint ."
  },
  "dependencies": {
    "axios": "^0.19.0",
    "buffer": "^5.2.1",
    "crypto-js": "^3.1.9-1",
    "jetifier": "^1.6.3",
    "jsencrypt": "^3.0.0-rc.1",
    "mobx": "^5.11.0",
    "mobx-react": "^5.4.4",
    "moment": "^2.24.0",
    "native-base": "^2.12.1",
    "prop-types": "^15.7.2",
    "querystring": "^0.2.0",
    "react": "16.8.6",
    "react-native": "0.60.3",
    "react-native-config": "^0.11.7",
    "react-native-date-picker": "^2.7.3",
    "react-native-device-info": "2.3.2",
    "react-native-exception-handler": "^2.10.8",
    "react-native-gesture-handler": "^1.4.0",
    "react-native-keyboard-spacer": "^0.4.1",
    "react-native-linear-gradient": "^2.5.4",
    "react-native-modal": "^11.1.0",
    "react-native-modal-dropdown": "^0.6.2",
    "react-native-picker-select": "^6.3.0",
    "react-native-popup-dialog": "^0.18.2",
    "react-native-reanimated": "^1.4.0",
    "react-native-root-toast": "^3.1.2",
    "react-native-screens": "^2.0.0-beta.10",
    "react-native-scrollable-tab-view": "^0.10.0",
    "react-native-splash-screen": "^3.2.0",
    "react-native-sqlite-storage": "^3.3.11",
    "react-native-tab-view": "^2.8.0",
    "react-native-user-agent": "^1.0.4",
    "react-native-user-inactivity": "^1.0.1",
    "react-native-uuid": "^1.4.9",
    "react-native-wheel-picker-android": "^2.0.5",
    "react-navigation": "^3.11.1"
  },
  "devDependencies": {
    "@babel/core": "^7.5.5",
    "@babel/plugin-proposal-decorators": "^7.4.4",
    "@babel/runtime": "^7.5.5",
    "@react-native-community/eslint-config": "^0.0.5",
    "babel-jest": "^24.8.0",
    "babel-plugin-transform-decorators-legacy": "^1.3.5",
    "babel-preset-react-native": "^4.0.1",
    "eslint": "^6.1.0",
    "jest": "^24.8.0",
    "metro-react-native-babel-preset": "^0.55.0",
    "react-test-renderer": "16.8.6"
  },
  "jest": {
    "preset": "react-native"
  }
}

As i am new to react native please let me know if more information needed in question?

Thank you for help

Answer 1

Sometimes it can load an old version of the code and not updating. For me sometimes just \android\gradlew clean and react-native run-android (from the main folder) works.

I don't know if it solves your problem but it worth a try. A lot of errors in react-native can be solved by gradlew clean and/or restarting your computer.

Answer 2

You need to compile the code first..

npm run dev

Or npm test