1. Sample of context-api with `react-hook` (`useContext`).
2. Know how to structure react native app with typescript.
3. Know how to navigate between screens with `react-navigation`.
4. Know how to write test code with `testing-library`.
5. Know how to `lint` your project with `eslint` for both `ts` and maybe some `js`.
6. Know how to localize your project.

npm install && npm start
// or
yarn && yarn start

app/
├─ .doobooo // necessary if using dooboo-cli
├─ .expo
├─ assets
│  └─ icons // app icons
│  └─ images // app images like background images
├─ node_modules/
├─ src/
│  └─ apis
│  └─ components
│     └─ navigations
│     └─ screen
│     └─ shared
│  └─ contexts
│  └─ utils
│  └─ App.tsx
├─ test/
├─ .buckconfig
├─ .flowconfig
├─ .gitattributes
├─ .gitignore
├─ .watchmanconfig
├─ app.json
├─ babel.config.js
├─ index.js
├─ jest.config.js
├─ package.json
├─ README.md
├─ STRINGS.js
├─ tsconfig.json
└─ tslint.json

> jest -u

 PASS  src/components/shared/__tests__/Button.test.tsx
 PASS  src/components/screen/__tests__/Intro.test.tsx
 › 2 snapshots written.

Snapshot Summary
 › 2 snapshots written in 1 test suite.

Test Suites: 2 passed, 2 total
Tests:       5 passed, 5 total
Snapshots:   2 added, 4 passed, 6 total
Time:        3.055s, estimated 6s
Ran all test suites

import * as Localization from 'expo-localization';
import i18n from 'i18n-js';

const en = {
  HELLO: 'Hello',
  LOGIN: 'Login',
  EMAIL: 'Email',
  PASSWORD: 'Password',
  SIGNUP: 'SIGN UP',
  FORGOT_PW: 'Forgot password?',
  NAVIGATE: 'Navigate',
  CHANGE_THEME: 'Change theme',
};

const ko = {
  HELLO: '안녕하세요',
  LOGIN: '로그인',
  EMAIL: '이메일',
  PASSWORD: '패스워드',
  SIGNUP: '회원가입',
  FORGOT_PW: '비밀번호를 잊어버리셨나요?',
  NAVIGATE: '이동하기',
  CHANGE_THEME: '테마변경',
};

i18n.fallbacks = true;
i18n.translations = { en, ko };
i18n.locale = Localization.locale;

export const getString = (param: string, mapObj?: object) => {
  if (mapObj) {
    i18n.t(param, mapObj);
  }
  return i18n.t(param);
};

import { NativeModules } from 'react-native';

/**
 * monkey patching the locale to avoid the error:
 * Something went wrong initializing the native ReactLocalization module
 * https://gist.github.com/MoOx/08b465c3eac9e36e683929532472d1e0
 */

NativeModules.ReactLocalization = {
  language: 'en_US',
};

"eslint.enable": true,
"eslint.validate": [
    "javascript",
    "javascriptreact",
    "typescript",
    "typescriptreact"
],
// prettier extension setting
"editor.formatOnSave": true,
"[javascript]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
},
"[javascriptreact]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
},
"[typescript]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
},
"[typescriptreact]": {
    "editor.defaultFormatter": "esbenp.prettier-vscode"
},
"prettier.singleQuote": true,
"prettier.trailingComma": "all",
"prettier.arrowParens": "always",
"prettier.jsxSingleQuote": true