LoadFileUrl and LoadHtmlString not loading local document resources - ios

Question

Basically using HybridWebView which uses WKWebview I'm loading a downloading an html file with a bunch of css files that are stored in the app documents directory.
Example
var/mobile/Containers/Data/Application/C9D9BB56-79B6-4990-A599-18C6AD928A22/Documents
I can load the html just fine using LoadFileUrl or LoadHTMLString, the issue is that the referenced css and js does not load into the webview
This is my file url
file:///var/mobile/Containers/Data/Application/C9D9BB56-79B6-4990-A599-18C6AD928A22/Documents/Courses/2d7d0a7d-145a-41d0-9abf-685a2b5dfc3c/Online_Placement_Test_no_timer_pack/YKZOP4NACH3EPJNTG6M4T2BQDI/Unit_4_5/995/Unit.html
Base Url
file:///var/mobile/Containers/Data/Application/C9D9BB56-79B6-4990-A599-18C6AD928A22/Documents/Courses/2d7d0a7d-145a-41d0-9abf-685a2b5dfc3c/Online_Placement_Test_no_timer_pack/YKZOP4NACH3EPJNTG6M4T2BQDI/Unit_4_5/995/
And this is an example of a path to a resource that doesn't load grabbed from the network inspector in Safari.
file:///var/mobile/Containers/Data/Application/C9D9BB56-79B6-4990-A599-18C6AD928A22/Documents/Courses/2d7d0a7d-145a-41d0-9abf-685a2b5dfc3c/Online_Placement_Test_no_timer_pack/YKZOP4NACH3EPJNTG6M4T2BQDI/Unit_4_5/995/js/bootstrap.min.js
Not sure what I'm doing wrong here. I've even set
<key>NSAppTransportSecurity</key>
<dict>
<key>NSAllowsLocalNetworking</key>
<true/>
<key>NSAllowsArbitraryLoads</key>
<true/>
</dict>
in info.plist

Answer 1

You can obtain the doc dir via NSFileManager.DefaultManager.GetUrl.
Example loading "WebSite" from App's document directory
var docsDir = NSFileManager.DefaultManager.GetUrl(NSSearchPathDirectory.DocumentDirectory, NSSearchPathDomain.User, null, true, out var error);
var data = NSUrl.FromFilename(Path.Combine(docsDir.Path, "WebSite", "index.html"));
var content = NSUrl.FromFilename(Path.Combine(docsDir.Path, "WebSite"));
webView.LoadFileUrl(data, content);
Example loading "WebSite" from bundled resources:
var bundlePath = NSBundle.MainBundle.BundlePath;
var data = NSUrl.FromFilename(Path.Combine(bundlePath, "WebSite", "index.html"));
var content = NSUrl.FromFilename(Path.Combine(bundlePath, "WebSite"));
webView.LoadFileUrl(data, content);
Using an downloaded Azure sample website
Note: Downloaded to a WebSite subdir within NSSearchPathDirectory.DocumentDirectory
├── css
│   └── site.css
├── fonts
│   └── segoeuil.ttf
├── img
│   ├── cloneWhite.svg
│   ├── deployWhite.svg
│   ├── lightbulbWhite.svg
│   ├── stackWhite.svg
│   ├── successCloudNew.svg
│   └── tweetThis.svg
└── index.html
Local Output:

Answer 2

Loading a locally stored website or html-File from the filesystem's App's caches directory using WebKit WKWebView in Objective-C in iOS13
Note the very important webView.configuration.preferences setting allowFileAccessFromFileURLs!!
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *docsDir = [paths objectAtIndex:0];
NSString *downloadDir = [[NSString alloc] initWithFormat:#"%#/%#", docsDir, #"www"];
NSURL* downloadDirUrl = [[NSURL alloc] initFileURLWithPath:downloadDir];
NSLog(#"DIR '%#'", downloadDirUrl);
NSURL* indexHtmlUrl = [[NSURL alloc] initWithString:[[NSString alloc] initWithFormat:#"%#/%#", downloadDir, #"/index.html?param=val"]];
NSLog(#"HTML '%#'", indexHtmlUrl);
WKWebView* webView = ...;
[webView.configuration.preferences setValue:#YES forKey:#"allowFileAccessFromFileURLs"];
[webView loadFileURL:indexHtmlUrl allowingReadAccessToURL:downloadDirUrl];