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I'm developing an web HTML5 application for the iPhone and I'm stuck at a rather wierd situation. I need to cache the whole thing for offline usage and that's fine, but the thing is, when you are online later it still uses the cache version. I need the app to use the online version instead of the cached version when it can, but I don't manage to find any info on doing that.

Thanks in advance!

Johan S
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  • Duplicate of [html5-use-cache-only-when-offline](http://stackoverflow.com/questions/9343908/html5-use-cache-only-when-offline). –  Apr 13 '14 at 15:27

1 Answers1

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I don't know what framework you are using, but in Sencha, you need to specify to use the network by doing something like this:

NETWORK:
*

If you have things in your manifest file, it will always use that cached copy, which is what you are experiencing. So that is the default behavior for items that are in your manifest file.

Now, it gets a little trickier.

Article: http://www.sencha.com/learn/taking-sencha-touch-apps-offline/

In this Sencha offline example, they set a proxy for cached database, and then switch between the browser cache and the local storage.

Then, you want to create a listener without a timeout to detect if you are offline or online.

If you timeout, then use the local proxy. Like this:

this.onlineStore.addListener('load', function () {
    console.log("I think we are online");
    helloWorld.offlineStore.proxy.clear();
    this.each(function (record) {
        var photo = helloWorld.offlineStore.add(record.data)[0];
    });
    helloWorld.offlineStore.sync();
    helloWorld.gallery.bindStore(helloWorld.offlineStore);
});
User970008
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  • So if an app is online but has cached a copy of for example index.html when I visit www.example.com/index.html you can't access that unless the user removes index.html from their cache? – Johan S Mar 10 '12 at 21:55
  • I'm not using any framework except a bit jquery mobile, but only when it's necessary. – Johan S Mar 10 '12 at 21:55
  • There are two caches. Browser cache for pages and images. And then the application cache. If you specify an asset in your manifest file, it will be cached for the application. It will be a part of the application that is saved on the local device. So if you declare a javascript file to be a part of the application, it will cache that js file. Your example of index.html will be cached in the browser automatically unless you declare it in your manifest file. The catch with the browser cache is that it will obey the settings you have set for it. – User970008 Mar 11 '12 at 00:56
  • So, since that html file is not in the manifest, your browser will be responsible for the cache. – User970008 Mar 11 '12 at 00:57
  • Still, there is no way to tell a web app to use online content when available or otherwise the cached version? – Johan S Mar 11 '12 at 12:44
  • I just saw this was a double - post, http://stackoverflow.com/questions/9343908/html5-use-cache-only-when-offline – Johan S Mar 11 '12 at 12:46
  • Hi, Yes, there is a way. I edited my answer using the Sencha example. – User970008 Mar 11 '12 at 13:03