manifest should be queried when app is launched from home screen

[laurentperez]

I've tested https://github.com/GoogleChrome/samples/tree/gh-pages/web-application-manifest under Chrome 39+, Add to home screen works.

However, the manifest.json is not queried when I run the app from the home screen. If I change a manifest property like orientation, it will not update. If I run the page again from Chrome, Add to home screen creates a second icon, now I have two icons for my app, one in landscape, the other one in portrait.

I believe add to home screen should create some application hash based on relevant manifest properties (say, name) so that it could detect I want to update an existing home screen app, instead of creating a second link. For this to work, the manifest should be queried on app launch, and it should also update.

What do you think ?

[marcoscaceres]

Duplicate of: #272

@laurentperez what you are describing about updates is currently a limitation in Chrome's implementation. The spec contains some text already about performing updates, but you are correct that it doesn't speak about the identity problem - so will absolutely add something to the spec (will probably reuse some of what you wrote to explain the use case :) ).

The problems with trying to key an app off the manifest data is that the manifest is allowed to be empty. So, a manifest file with just "" or "{}" is totally valid.

It's probably better just to key it off the URL of the manifest, as suggested in #272.

[laurentperez]

yes, I noticed #272 afterwards. closing mine.