Unable to open asset URL: file:///android_asset/error.html

Question

I have a custom error page to show in a Webview, that is stored in the default asset folder C:\Users\User\StudioProjects\Appname\app\src\main\assets\error.html

In the onReceivedError method of a WebViewClient I load the page like this view.loadUrl("file:///android_asset/error.html");

It worked fine when I coded and tested it, however the weird thing is, I tested it again, the Webview showed this error
The webpage at file:///android_asset/error.html could not be loaded because: net::ERR_FILE_NOT_FOUND

I tried the solution from https://stackoverflow.com/a/37994555/4722232, it worked for the html, but I have a logo in it and having the same problem and in the log I'm getting

"Not allowed to load local resource: file:///android_asset/logo.png", source: about:blank (0)

Any help would be greatly appreciated

An image (drawable) file goes into `drawable-*` folder. I also check your uri and there was nothing wrong with it. make sure to put your HTML in asset that is located in `main` folder. You can right click on `app` then `new` and `folder` and `asset folder` to put it in correct directory. — Arrowsome, Jun 25 '20 at 16:36
@abstractArrow yes I did that, and it also worked ok the first time I coded it — Filoména Petržlénová, Jun 25 '20 at 16:43
I will post an answer shortly that introduces two alternatives — Arrowsome, Jun 25 '20 at 16:49
@IgorGanapolsky Not really, I stopped displaying the error page for now. But I might try turning the html into string and get the resource using Html.fromHtml(getString(...)). — Filoména Petržlénová, Oct 19 '20 at 11:50

score 1 · Answer 1 · answered Jun 25 '20 at 16:59

1

Read the file from asset and load into WebView

val htmlFile = "file:///android_asset/file_name.extension" //e.g. index.html
webView.loadUrl(htmlFile)

asset folder must be inside main

Get the content of the file from the asset folder and then load into WebView

val inputStream = assets.open("file_name.extension")
val buffer = BufferedInputStream(inputStream)
val bytes = buffer.readBytes()
val content = String(bytes)
buffer.close()
webView.loadData(String(content), "text/html", "utf-8")

Read the file from raw folder

res -> raw -> file_name.extension

val inputStream = resources.openRawResource(R.raw.index)
val buffer = BufferedInputStream(inputStream)
val bytes = buffer.readBytes()
val content = String(bytes)
buffer.close()
webView.loadData(String(content), "text/html", "utf-8")

You can use Kotlin Extensions to streamline this process

assets.open("file_name.extension").bufferedReader().use { br ->
    webView.loadData(br.readText(), "text/html", "utf-8")
}

Make sure your file_name.extension be lowercase and only contain _ if they are in either res or assets folder.

answered Jun 25 '20 at 16:59

Arrowsome

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Thank you for the answer. I used the inputStream, the html file works now, but my image is still not getting displayed. I moved the image to `main\res\drawable`. Would the path to it then be `` ? – Filoména Petržlénová Jun 25 '20 at 17:49
@FiloménaPetržlénová Now I get it. you are using the image for HTML file and that's okay to put it inside the `assets` folder. put it back in `assets` folder and that exact location depends on `` inside your HTML. so the `assets` folder is your root folder. – Arrowsome Jun 25 '20 at 18:14
yes, I had it in the asset folder, but I still got the `Unable to open asset URL: file:///android_asset/logo.png` error. In the html file it was like this `` – Filoména Petržlénová Jun 26 '20 at 10:12
@FiloménaPetržlénová Share your HTML file if possible so I can test it locally. – Arrowsome Jun 26 '20 at 10:15

Unable to open asset URL: file:///android_asset/error.html

1 Answers1