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google-nativeclient

Could Native Client web application create windows and common controls while runtime?

I talking about Native Client thing for google chrome...
Developers claim it can run native code compiled from c / c++ in browser's sandbox.
They describe a lot of things, but never point at what I need... So, if I create window in my application with CreateWindow, would this window appear when my Native Client application loaded into browser?

Solution

  • In short, no. Two key things to know about apps that use Native Client in Chrome:

    1. They are platform independent (platform-specific calls are disallowed).
    2. They are still web apps with the restrictions and possibilities that come with that.

    If Native Client allowed operating system-specific calls like CreateWindow, it would no longer be platform independent (and it would also present a security risk).

    Instead Native Client provides a set of platform-independent APIs called Pepper or PPAPI that work the same for all supported operating systems (currently that's Mac OS, Windows, Linux, and Chrome OS). As mentioned, apps that use Native Client are still web apps, so Pepper gives the same possibilities and restrictions that you'd expect from JavaScript. E.g., you can fetch URLs or ask the user for fullscreen permission, but you cannot access any random file from the local file system (app-specific isolated local storage is possible; as is having the user upload a file for the app to use).

    Moving an existing C or C++ codebase to Native Client is very much like porting to a different operating system. Instead of using, say, Windows API calls, your app should use Pepper API calls.

    For additional background it may be worth noting that Chrome Packaged Apps can request access to a much wider set of APIs in the chrome.* namespace. These APIs include USB, sockets, opening new windows, and more. A Chrome Packaged App will still not be allowed to make OS-specific calls, but they have access to quite a few more APIs, all of which are platform-independent.

    In short, if your app can be made to work with the Pepper API plus the chrome.* APIs, you could write it in Native Client and JavaScript, and you'd have an app that worked the same way across the four operating systems mentioned above. If your app cannot be made to work with those APIs, Native Client in Chrome is not the right choice.