react-cross-platform-cli

react-cross-platform-cli

This project serves as a simple command line interface. One can use it to generate a boilerplate project for a cross platform react application.

Included platforms

The following platforms are supported in the boilerplate application:

• Android (using react-native)
• iOS (using react-native)
• Web / Browser (using react-native-web)
• Desktop Application (using electron)

Installation

Install the CLI globally on your machine using npm:

npm install -g react-cross-platform-cli

The recommended package manager is yarn. If you don't have it installed, you can let the CLI do it for you. If you don't want to use yarn, the CLI will go on using npm as package manager.

The CLI uses react-native-cli to initialize the application. You can either install react-native-cli manually or let the CLI do this for you.

Usage

To run the CLI simply type

react-cross-platform-cli init

The CLI will ask you for a project name and the platforms you want to use. (Android and iOS are always default, Web and Desktop are optional.)

The CLI then creates a new folder in your working directory with the boilerplate application. In app.json you can specify displayName which will be the name of your application in production.

The single source of truth for all devices is the App Component located in app.js. Simply use this as your main component and import all custom components there, then you never should have to actually touch any of the platform-specific files.

Android

The following scripts are created by the CLI:

Script	Description
npm run android	Runs the React Native package.
npm run android:build	Runs the React Native packager, builds your application for development and installs it on the virtual or physical device.
npm run android:build:app	Builds your application for production.
npm run android:clean	Removes files of previous builds.

Setup

To run your app on a physical or emulated android device you have to setup Android Studio. For extended instructions on doing so, look up the React Native Getting Started page.

Developing

To start developing open up your Android Virtual Device or connect your physical device. Notice that React Native requires you to run Android 6.0 (Marshmallow), so make sure you are using this.

To initially build your application run npm run android:build. This may take a while, depending on your resources. This will also open up a new termial running the React Native packager. When it's done, the app should automatically open up on your device.

After you changed your code, go back to the AVD and hit R+R (double-tap R) to reloade the application.

When you already initially built the application, it is enough to just start the packager with npm run android. When you open up the application on your devive, reloading it like above should work just fine.

If you want to remove any files from previous build, you can do so by running npm run android:clean. (Not that this won't remove the installation from your AVD.)

Building for production

On Android devices you need to sign your application before you actually can distribute them. The React Native documentation should provide you with instructions for that.

When you added your keys, just run npm run android:build:app to build the release apk. You can find it in android/app/build/outputs/apk.

iOS

The following scripts are created by the CLI:

Script	Description
npm run ios	Runs the React Native package.
npm run ios:build	Runs the React Native packager, opens your iPhone simulator, builds your application and installs it on the virtual device.
npm run ios:clean	Removes files of previous builds.

Setup

To develop your application for iOS you only need Xcode. (Note that this is only available via the AppStore for devices running MacOS.)

Developing

To start developing just run npm run ios:build to initially build the application. This may take a while, depending on your resources. It will open up a new termial running the React Native packager and your iPhone simulator. When it's done, the application should automatically open up on the simulator.

After you changed your code, go back to the simulator and hit Cmd+R to reloade the application.

When you already initially built the application, it is enough to just start the packager with npm run ios. When you open up the application on the simulator, reloading it like above should work just fine.

If you want to remove any files from previous build, you can do so by running npm run ios:clean. (Not that this won't remove the installation from your simulator.)

Building for production

React Native automatically generates and maintaines a Xcode project for you. The documentation provides instructions how to use Xcode to build your application for production.

Web / Browser

The following scripts are created by the CLI:

Script	Description
npm run web	Runs webpack-dev-server and serves your application on http://localhost:3000.
npm run web:build	Builds your whole application for production.
npm run web:build:app	Builds your application and any implicit vendored libraries.
npm run web:build:vendor	Builds the react-native-web library for production.
npm run web:build:vendor-dev	Builds the react-native-web library for development.
npm run web:clean	Removes files of previous builds.
npm run web:serve	Opens your production build on http://localhost:3001.

Developing

Starting development for web should be as easy as running npm run web. This will start webpack-dev-server. Once it has compiled your code, you should be able to access the application under http://localhost:3000.

Port 3000 is used by default, but you can change this easily in your package.json file.

You can remove all compiled files by running npm run web:clean.

Building for production

To build your application for production run npm run web:build. You can find all the html and js files for your frontend under web/build.

You can serve the production build to http://localhost:3001 by running npm run web:serve. Again you can change the port by editing the script in the package.json file.

Desktop

The following scripts are created by the CLI:

Script	Description
npm run desktop	Opens your application for development in electron.
npm run desktop:build	Builds your desktop application for production using electron-packager.

Developing

If you run npm run desktop, this will start compiling the code using webpack-dev-server. In addition a electron window opens that displays your application.

Notice that those two processes start in parallel. You won't see any output until webpack has finished compiling. You can reload the window with Cmd+R on MacOS and Ctrl+R on Windows and Linux.

Building for production

By running npm run desktop:build your application gets compiled into an executable for your current operating system (i.e. a .exe for Windows and so on). The script uses electron-packager to do this.

Credits

• For directly initializing the react-native-application I use the react-native-cli.
• For building the desktop application in production electron-packager is used.
• For all the rest I mostly based this on this project by ndbroadbent.