الخميس، 19 ديسمبر 2013

Keeping Chrome Extensions Simple

القسم
Today we're announcing an update to the Chrome Web Store policy: extensions in the Chrome Web Store must have a single purpose that is narrow and easy-to-understand. While this has always been the intent of the Chrome extension system, not all extensions have lived up to this ideal. These multi-purpose extensions can crowd your browser UI and slow down your web browsing - sometimes significantly. We're making this policy change to fix these problems and give users more control over their browsing experience.

A simple and speedy browsing experience has been part of the core principles of Chrome since the beginning. Simplicity was important to us because browsers had become overly complex, with bulky user interfaces (commonly referred to in the industry as "chrome"). That detracted from the content of the page, which was the whole point of the browser. The name "Chrome" came from this principle as we wanted the browser to be about "content, not chrome."

One significant contributor to the excess of browser chrome at the time were extensions like the then-ubiquitous toolbar. When users installed more than one of these toolbars, the results could be overwhelming.


To keep with our principle of simplicity, we decided to take a different approach. Chrome extensions would be simple and single-purpose in nature, and each would only be allowed a single visible UI "surface" in Chrome, a single browser action or page action button. Toolbars wouldn't be supported by design, and users would have more control over which features they added to their browser.

Unfortunately, in some cases, we couldn't enforce these design goals technically. With content scripts, extension developers have full control over the page, so they can put up as much UI as they want, even going as far as to create toolbars in the page. Others used content scripts to create extensions with more subtle features bundled together that were harder to attribute to specific extensions. In many cases, the Chrome Web Store helped by showing poor reviews when users had noticed bad behavior from a particular extension, but in other cases the connection wasn't clear.

Even worse, when extensions were sideloaded locally on their computer (perhaps bundled as part of another piece of software they installed) the user wouldn't have the benefit of the information in the Chrome Web Store at all, so they might not realize they were agreeing to install an extension with unwanted functionality or poor reviews.

It is for these reasons that we've updated the Chrome Web Store policy to enforce our original single-purpose design goal for extensions. We realize that this will require significant changes for some existing extensions. Some may need to be split into multiple separate extensions. Developers may need to switch to a different approach to monetization, which we've recently made easier by adding payment options to extensions. Since these changes may take some time to implement, we're not going to start enforcing the policy for existing extensions in the Web Store until June 2014. For new extensions, the policy will go into effect immediately.

If you have any questions, please find us in our G+ community, on Stack Overflow, or our mailing list.

Posted by Erik Kay, Engineering Director

الخميس، 12 ديسمبر 2013

Ecma forms TC52 for Dart Standardization

القسم
This week Ecma created a new technical committee named TC52 to publish a standard specification of the Dart language. We�re excited about this milestone in the evolution of Dart and the web.

Dart is ready for standardization. As of last month�s 1.0 SDK release, Dart is now officially stable and mature enough for production use. We�ll be collaborating with the broader web community via TC52 to responsibly evolve the language going forward.

The new standardization process is an important step towards a future where Dart runs natively in web browsers. Dart apps can be fast when compiled to JavaScript, but an embedded Dart VM enables even better performance.

We're thrilled to have a dedicated technical committee working on Dart. We also feel confident that Ecma�the home of standards such as JavaScript, Eiffel, and C#�is the right place to help guide the evolution of the Dart language. If you�d like to get involved, please join the committee.

Posted by Anders Sandholm, Product Manager and Standard Guy

الثلاثاء، 3 ديسمبر 2013

Chrome DevTools for Mobile: Emulate and Screencast

القسم
Modern web apps are expected to render and perform on mobile perfectly. That means considering responsive design, 60 fps and connectivity early in the development cycle. With the Beta channel of Chrome for Android and desktop, we�ve made it easier to develop and debug mobile web apps through an improved viewport emulation and zero-config, screencast-enabled remote debugging.

While designing your app, you want to make sure it looks great on multiple screens. DevTools now enables you to go through the popular device screens without leaving the development environment. Just select a device from the Console drawer�s Emulation tab1 and all the relevant viewport properties will be set for you. We'll run the page through the same mobile viewporting code used in mobile Chrome to get you accurate results. You also have full control of the emulation parameters, such as screen resolution, touch emulation, devicePixelRatio, user agent, sensors and many more.


But what if you need to test the actual web app's performance on a real device?

Chrome Beta � including ChromeOS � now supports native USB discovery of connected devices. Find them under Tools ? Inspect Devices menu item, or visit the about:inspect page. There�s no configuration necessary and no need for the adb command line tool or extensions to see all instances of Chrome and WebView on the devices connected to your computer2.

While connected over USB, you can screencast the full viewport content from the device to DevTools. The corresponding icon will be shown next to the Elements tab if the inspected device is able to screencast.


Keyboard and mouse events are also sent from DevTools to your device, so you don't even need to touch it while you're testing your apps.



Improved mobile emulation, USB debugging and screencast make it easier to develop, inspect and debug your mobile applications with DevTools. Have a look at Paul Irish�s talk from the Chrome Dev Summit 2013 for a hands-on demo of these features.

Posted by Pavel Feldman, Software Engineer and Viewport Teleporter

1 You need to check �Show 'Emulation' view in console drawer� in DevTool�s Settings? Overrides to enable the emulation features
2 Windows users need to install the USB device drivers to enable device communication