［React Native 笔记］几个命令行工具作用备忘

Requirements

1. OS X - This guide assumes OS X which is needed for iOS development.
2. Homebrew is the recommended way to install Watchman and Flow.
3. Install Node.js 4.0 or newer.
   • Install nvm with its setup instructions here. Then run nvm install node && nvm alias default node, which installs the latest version of Node.js and sets up your terminal so you can run it by typing node. With nvm you can install multiple versions of Node.js and easily switch between them.
   • New to npm?
4. brew install watchman. We recommend installing watchman, otherwise you might hit a node file watching bug.
5. brew install flow, if you want to use flow.

We recommend periodically running brew update && brew upgrade to keep your programs up-to-date.

Homebrew: 跟Linux的yum同样的东西，命令就是brew
NPM（node package manager），通常称为node包管理器。顾名思义，它的主要功能就是管理node包，包括：安装、卸载、更新、查看、搜索、发布等。
（安装办法：https://github.com/creationix/nvm#installation）
npm install XXX
npm uninstall XXX
-g 是指安装到全局，否则安装到本目录下

iOS Setup

Xcode 7.0 or higher is required. It can be installed from the App Store.

Android Setup

To write React Native apps for Android, you will need to install the Android SDK (and an Android emulator if you want to work on your app without having to use a physical device). See Android setup guide for instructions on how to set up your Android environment.

NOTE: There is experimental Windows and Linux support for Android development.

Quick start

Install the React Native command line tools:

$ npm install -g react-native-cli

cli是指啥意思？

NOTE: If you see the error, EACCES: permission denied, please run the command: sudo npm install -g react-native-cli.

Create a React Native project:

$ react-native init AwesomeProject

To run the iOS app:

• $ cd AwesomeProject
• Open ios/AwesomeProject.xcodeproj and hit run in Xcode.
• Open index.ios.js in your text editor of choice and edit some lines.
• Hit ⌘-R in your iOS simulator to reload the app and see your change!

Note: If you are using an iOS device, see the Running on iOS Device page.

To run the Android app:

• $ cd AwesomeProject
• $ react-native run-android
• Open index.android.js in your text editor of choice and edit some lines.
• Press the menu button (F2 by default, or ⌘-M in Genymotion) and select Reload JS to see your change!
• Run adb logcat *:S ReactNative:V ReactNativeJS:V in a terminal to see your app's logs

Note: If you are using an Android device, see the Running on Android Device page.

Congratulations! You've successfully run and modified your first React Native app.

If you run into any issues getting started, see the troubleshooting page.

Adding Android to an existing React Native project

If you already have a (iOS-only) React Native project and want to add Android support, you need to execute the following commands in your existing project directory:

1. Update the react-native dependency in your package.json file to the latest version
2. $ npm install
3. $ react-native android

Upgrading

Edit on GitHub

Upgrading to new versions of React Native will give you access to more APIs, views, developer tools and other goodies. Because React Native projects are essentially made up of an Android project, an iOS project and a JavaScript project, all combined under an npm package, upgrading can be rather tricky. But we try to make it easy for you. Here's what you need to do to upgrade from an older version of React Native:

1. Upgrade the react-native dependency 

Note the latest version of the react-native npm package from here (or use npm info react-native to check):

• https://www.npmjs.com/package/react-native

Now install that version of react-native in your project with npm install --save. For example, to upgrade to the version 0.18, in a terminal run:

$ npm install --save react -native@ 0.18

2. Upgrade your project templates 

The new npm package will likely contain updates to the files that are normally generated when you run react-native init, like the iOS and the Android sub-projects. To get these latest changes, run this in a terminal:

$ react -native upgrade

This will check your files against the latest template and perform the following:

• If there is a new file in the template, it is simply created.
• If a file in the template is identical to your file, it is skipped.
• If a file is different in your project than the template, you will be prompted; you have options to view a diff between your file and the template file, keep your file or overwrite it with the template version. If you are unsure, press h to get a list of possible commands.

Manual Upgrades 

Xcode project format is pretty complex and sometimes it's tricky to upgrade and merge new changes.

From 0.13 to 0.14 

The major change in this version happened to the CLI (see changelog) and static images (see docs). To use the new asset system in existing Xcode project, do the following:

Add new "Run Script" step to your project's build phases:

Set the script to

. . /node_modules /react -native /packager /react -native -xcode .sh

Move main.jsbundle to Trash (it will be generated automatically by Xcode using the script above)

If you installed Node via nvm, you might experience "react-native: command not found". See issues/3974 for workaround and pull/4015 for the fix.