I'm trying to develop an application using UIWebView. The app is loading remote URL's, so in order to make it quick I want it to use the images included in the application bundle. I was wondering if there is a way to do it without forcing the application to manually replace the address of each image to point into local resources?
I doubt it, unfortunately. Browser security models in general (and this applies to browsers on the desktop as well of course) don't allow file:// scheme URLs to be used in the context of any other scheme (http://) page. If this was allowed, then arbitrary sites you browse to could load local files and possible access private user data, which would be Bad. Local images with the file:// scheme will only work in a page that is itself in the file:// domain.
I'm not sure how to tell you to accomplish this, but perhaps someone else has a clever idea.
You can use this:
Stop Images from loading in UIWebView
...which sounds horrendous, but is actually quite easy to do, and lets you replace requests for the remote URL with a hit to the local URL.
You'll have to convert the URLs manually, of course.
Related
I am developing an application for a client where a requirement is that a series of complex (multi-file, JS, CSS, etc), websites must be presented offline, without any web connection required at all.
So I have all of the HTML content folders, and can add them into my XCode project... but now I need to show them.
The UIWebView is fine when you just have one HTML file... but the relative paths for the JS and CSS do not translate over.
What is the best way to do this. I've seen a couple of potential choices. One way is to run a super basic web server locally, dump all the files into /documents (or thereabouts) and serve it from there... the second is to somehow make UIWebView re-interpret the paths so that they point to the right place locally... which I am not sure if it's possible but I've seen it alluded to.
Seems like a lot of people just cover loading a single UIWebView page, and not so much discussing how to deal with CSS/JS dependencies.
Anyone have any bright ideas, links, etc?
Thanks
I think that if you add your HTML/CSS/JS tree to your Xcode project and select "Create folder references for any added folder" (instead of "Recursively create groups for any added folders"), then your bundle will contain the HTML/CSS/JS folder hierarchy (instead of the flattened-out list of all files). This would preserve relative paths.
As to the "reinterpreting" point, you can define
– webView:shouldStartLoadWithRequest:navigationType:
in your UIWebViewDelegate to intercept any attempt at loading any file. There you can change the url on the fly.
Also, have a look at this interesting article by Rob Napier: Drop-in offline caching for UIWebView.
I am doing some updates to a site I have developed over the last few years. It has grown rather erratically (I tried to plan ahead, but with this site it has taken some odd turns).
Anyway, the site has a community blog ( blog.domain.com - used to be domainblog.com) ) and users with personal areas ( user1.domain.com, user2.domain.com, etc ).
The personal areas have standard page content that the user can use, or add snippets of text to partially customize. Now the owner wants the users to be able to create their own content.
Everything is done up to using a file browser.
I need a browser that will allow me to do the following:
the browser needs to be able to browse the common files at blog.domain.com/files and the user files at user_x.domain.com/files
the browser will also need to be able to differentiate between the two and generate the appropriate image url.
of course, the browser access to the user files will need to be dynamic and only show those files particular to the user (along with the common files)
I also need to be able to set a file size for images
the admin area is in a different directory than either the blog or the user subdomains.
general directory structure
--webdir--
|--client --
|--clientsite--
|--blog (blog.domain.com)
|--sites--
|--main site (domain.com)
|--admin (admin.domain.com)
|--users--
|--user1 (user1.domain.com)
|--user2 (user2.domain.com)
...etc.
I have tried several different browsers and using symlinks but the browsers don't seem to be able to follow them. I am also having trouble even setting them to use a directory that isn't the default.
what browser would you recommend? what would I need to customize to make it work.
TIA
ok, since I have not had any responses to this question, I guess I will have to do a work around and then see about writing a custom file browser down the road.
I would like to save a .html webpage with AFNetworking, but would also like to save the resources (such as .css files, .js files, images etc) within the webpage so that the whole webpage can be viewed offline.
Is this possible with AFNetworking, and how would I do it? Could a short example be posted please?
Thanks!
AFNetworking is not necessary to do this. Instead, what you want to do is use an NSURLCache subclass that supports disk cacheing (such as Peter Steinberger's fork of SDURLCache). With that in place, just load up a URL using a UIWebView (this may not necessarily have to be displayed to a user), and subsequent loads should use that local cache.
At the very least, do not waste your time trying to write something on your own to download assets on a webpage. This process requires a web browser (which UIWebView qualifies as) to determine everything needed to load.
I am trying to solve 2 things in my UIWebView:
Load local assets in place of remote ones, under the right conditions
Load remote assets as normal if there are no local ones or they are outdated
Allow the webview to go "back" without needing to reload it's html form the server
So to handle #1 and #2, I implemented a custom subclass NSURLCache. It gets called when the webview requests assets, and I can send along the local ones instead, aborting the server call for the asset. I even have a little timestamping system that knows if the local version is old or not to figure out which one to use.
But #3 is throwing me for a loop. It seems that regardless of cache-control headers, UIWebView will ALWAYS reload the HTML when going back.
So I tried to force caching of the HTML in my custom NSURLCache class. It seems to work, and returns the instance of NSCachedURLResponse with the HTML I want, but the UIWebView fails to notice and loads it from the server anyway. After some searching I see there is some "inconsistencies" with UIWebView and the url cache, and I guess this is one. Works great for assets, but not so great for the HTML that makes up the page it's trying to display.
So then I decided that since this may not work, do it manually. I created a stack of urls, and their data that I fetch manually and load it with loadData:MIMEType:textEncodingName:baseURL:. Lo and behold it seemed to work great! I could now go back, the web view delegate would intercept the load, and tell it to load my manually fetched data instead, and the server would not be hit.
However, then I noticed that the NSURLCache was no longer being used for my assets. It seems it only asks for cached assets if you load content with loadRequest: and not by loading data or an html string with the baseUrl set properly.
So despite all my efforts I cannot make a web view conditionally load local assets AND navigate back without hitting the server. It seems like I have a few bugs here in the SDK.
UIWebView ignores the servers Cache-Control header for HTML content
UIWebView asks for a NSCachedURLResponse's for the main HTML request but is then ignored and discarded.
UIWebView asks the NSURLCache for assets if you load it up with a request, but when loading with HTML or data it bypasses the cache completely and requests it directly from the remote server.
So first up, anyone see a solution to these things? And second, any reason that I am being stupid and these are not actually SDK bugs?
To tackle your first #3:
While it may seem a little unorthodox, how about persisting the downloaded HTML to an NSUserDefaults object as a flat string, and restoring it (conditionally) later when you need it?
I've abandoned this. There were just too many gotchas. Instead I just load new page in via ajax. And instead of [webview goBack] I have some custom javascript to do cool stuff for me on [webview stringByEvaluatingJavascriptFromString:#"goBack()"]
I want to bind my app to some file extension so when I receive an email with an attached file with the correct extension, clicking on it will launch my app and pass it the attached file.
Is it possible ? How ?
Thx
--G.
As iPhone applications are not allowed to share files on the file system, what you're looking for is not immediately possible (not with the published APIs that I know of, anyway). You might still have a couple of options though.
Either way you'll have to use a custom URL scheme, which is associated with your app, and paste that into your email. This URL might point to some external location, which your app can download the file from.
Or it might contain the actual file contents if it's fairly small. URLs are 'just text' (some restrictions apply), so you're free to put any data you want to in it, as long as it is URL-encoded.
You still need to get the URL into the email though, which might or might not be as easy as attaching a file.
It's not possible to simply associate a file extension with an application on the iPhone.
You could create a custom URL scheme that would launch your app, but probably that won't help you.
This is actually possible, I'm working on this exact same problem and this great tutorial has really helped me.