跨平台移动开发工具：Cordova VS Weex

I. Apache Cordova: http://cordova.apache.org

Overview
Apache Cordova is an open-source mobile development framework. It allows you to use standard web technologies - HTML5, CSS3, and JavaScript for cross-platform development. Applications execute within wrappers targeted to each platform, and rely on standards-compliant API bindings to access each device’s capabilities such as sensors, data, network status, etc.

Use Apache Cordova if you are:

a mobile developer and want to extend an application across more than one platform, without having to re-implement it with each platform’s language and tool set.

a web developer and want to deploy a web app that’s packaged for distribution in various app store portals.

a mobile developer interested in mixing native application components with a WebView (special browser window) that can access device-level APIs, or if you want to develop a plugin interface between native and WebView components.

Architecture
There are several components to a cordova application. The following diagram shows a high-level view of the cordova application architecture.

WebView
The Cordova-enabled WebView may provide the application with its entire user interface. On some platforms, it can also be a component within a larger, hybrid application that mixes the WebView with native application components. (See Embedding WebViews for details.)

Web App
This is the part where your application code resides. The application itself is implemented as a web page, by default a local file named index.html, that references CSS, JavaScript, images, media files, or other resources are necessary for it to run. The app executes in a WebView within the native application wrapper, which you distribute to app stores.

This container has a very crucial file - config.xml file that provides information about the app and specifies parameters affecting how it works, such as whether it responds to orientation shifts.

Plugins
Plugins are an integral part of the cordova ecosystem. They provide an interface for Cordova and native components to communicate with each other and bindings to standard device APIs. This enables you to invoke native code from JavaScript.

Apache Cordova project maintains a set of plugins called the Core Plugins. These core plugins provide your application to access device capabilities such as battery, camera, contacts, etc.

In addition to the core plugins, there are several third-party plugins which provide additional bindings to features not necessarily available on all platforms. You can search for Cordova plugins using plugin search or npm. You can also develop your own plugins, as described in the Plugin Development Guide. Plugins may be necessary, for example, to communicate between Cordova and custom native components.

NOTE: When you create a Cordova project it does not have any plugins present. This is the new default behavior. Any plugins you desire, even the core plugins, must be explicitly added.

Cordova does not provide any UI widgets or MV* frameworks. Cordova provides only the runtime in which those can execute. If you wish to use UI widgets and/or an MV* framework, you will need to select those and include them in your application.

Development Paths
Cordova provides you two basic workflows to create a mobile app. While you can often use either workflow to accomplish the same task, they each offer advantages:

Cross-platform (CLI) workflow: Use this workflow if you want your app to run on as many different mobile operating systems as possible, with little need for platform-specific development. This workflow centers around the cordova CLI. The CLI is a high-level tool that allows you to build projects for many platforms at once, abstracting away much of the functionality of lower-level shell scripts. The CLI copies a common set of web assets into subdirectories for each mobile platform, makes any necessary configuration changes for each, runs build scripts to generate application binaries. The CLI also provides a common interface to apply plugins to your app. To get started follow the steps in the Create your first app guide. Unless you have a need for the platform-centered workflow, the cross-platform workflow is recommended.

Platform-centered workflow: Use this workflow if you want to focus on building an app for a single platform and need to be able to modify it at a lower level. You need to use this approach, for example, if you want your app to mix custom native components with web-based Cordova components, as discussed in Embedding WebViews. As a rule of thumb, use this workflow if you need to modify the project within the SDK. This workflow relies on a set of lower-level shell scripts that are tailored for each supported platform, and a separate Plugman utility that allows you to apply plugins. While you can use this workflow to build cross-platform apps, it is generally more difficult because the lack of a higher-level tool means separate build cycles and plugin modifications for each platform.

When first starting out, it may be easiest to use the cross-platform workflow to create an app, as described in Create your first app guide. You then have the option to switch to a platform-centered workflow if you need the greater control the SDK provides.

II. Weex http://weex.apache.org/cn/

工作原理
Updated time: 14/06/2017
整体架构
Weex 表面上是一个客户端技术，但实际上它串联起了从本地开发环境到云端部署和分发的整个链路。开发者首先可以在本地像撰写 web 页面一样撰写一个 app 的页面，然后编译成一段 JavaScript 代码，形成 Weex 的一个 JS bundle；在云端，开发者可以把生成的 JS bundle 部署上去，然后通过网络请求或预下发的方式传递到用户的移动应用客户端；在移动应用客户端里，WeexSDK 会准备好一个 JavaScript 引擎，并且在用户打开一个 Weex 页面时执行相应的 JS bundle，并在执行过程中产生各种命令发送到 native 端进行的界面渲染或数据存储、网络通信、调用设备功能、用户交互响应等移动应用的场景实践；同时，如果用户没有安装移动应用，他仍然可以在浏览器里打开一个相同的 web 页面，这个页面是使用相同的页面源代码，通过浏览器里的 JavaScript 引擎运行起来的。

How it works

本地开发环境
Weex 的本地开发环境基于 web 开发体验而设计，web 开发者可以通过自己熟悉的 HTML/CSS/JavaScript 技术和语法实现移动应用的界面。同时 Weex 也对 Vue.js 这一非常优秀的前端框架做了官方的支持。

除此之外，Weex 的工程设计也是 web 开发者非常熟悉的，首先 web 开发者可以使用自己熟悉的 npm 进行依赖管理；其次 web 开发者在通过项目脚手架初始化工程、开发、调试、质量控制等各个环节，都可以参考 web 开发已有的最佳实践。

和如今 web 开发的最佳实践一样，Weex 会把一个页面的源代码全部编译打包成一个 JS bundle，在浏览器中，我们需要把这个 JS bundle 作为一段