[Android] Using ShowHtmlFile with HTML files stored at runtime

[omaRaad]

Service

• WebView

Version

2.2.6

Summary

Context

I have an HTML file stearmingAssets/html/WidgetTemplate.html. This file includes some placeholder text that is set at runtime to cater to different users(e.g. {APP_TOKEN} and {USER_ID}

I set these values at runtime by taking all the content from the WidgetTemplate.html and replacing the placeholders with the respective value. I then create a new file widget.html with the new content.

The Problem

On iOS, the whole process works smoothly. I can Write/Read into/from the streamingAssets path.
But on Android, it seems that it's read only. So I cannot do that. I have to write the file into the persisitentData path. And unfortunately, this path is not accepted by Gpm.WebView.

Any way to fix that?

Screenshots/Code

The code I use to read the template file:

    private IEnumerator LoadTemplate()
    {
        var htmlString = string.Empty;
        var htmlFile = Path.Combine(Application.streamingAssetsPath, "html/WidgetTemplate.html");
#if UNITY_IOS
        htmlString = File.ReadAllText(htmlFile);
        yield return null;
#elif UNITY_ANDROID
        var uri = "jar:file://" + Application.dataPath + "!/assets/html/WidgetTemplate.html";
        using (var www = UnityWebRequest.Get(uri))
        {
            yield return www.SendWebRequest();
            if (www.result != UnityWebRequest.Result.Success)
            {
                Debug.LogError(www.error);
                yield break;
            }

            htmlString = www.downloadHandler.text;
        }
#endif

        ShowHtmlString(htmlString);
    }

The code to write into a file and use with Gpm.

    public void ShowHtmlString(string htmlString)
    {
        htmlString = htmlString.Replace("{{APP_TOKEN}}", token)
                           .Replace("{{USER_ID}}", userId)
                           .Replace("{{WIDGET_TYPE}}", GetStringFromWidgetType(widgetType));

        string newWidgetFile = Path.Combine(Application.persistentDataPath, "Widget.html");
        Directory.CreateDirectory(Path.GetDirectoryName(newWidgetFile));
        File.WriteAllText(newWidgetFile, htmlString);

        string htmlFilePath = "file://" + newWidgetFile;

        GpmWebView.ShowHtmlFile(
            htmlFilePath,
            new GpmWebViewRequest.Configuration()
            {
                orientation = GpmOrientation.UNSPECIFIED,
                isClearCookie = true,
                isClearCache = true,
#if UNITY_IOS
                contentMode = GpmWebViewContentMode.MOBILE
#endif
            },
            OnCallback,
            new List<string>()
        );
    }

The error thrown by Gpm.WebView due to not using streamingAssets path for Android.

- [GPM][WebView][Android][WebViewManager] The custom scheme should be started by 'file:///android_asset/'.  (file:///storage/emulated/0/Android/data/com.bitburst.BitLabs/files/Widget.html)
- OnAsyncEvent : {"callback":0,"callbackType":0,"error":"{\"domain\":\"WebViewManager\",\"code\":\"INVALID_URL\",\"message\":\"Invalid file path.\"}","scheme":"gpmwebview://webViewCallback"}
- JsonException: Can't assign value 'INVALID_URL' (type System.String) to type System.Int32

Additional context

I can't use GpmWebView.ShowHtmlString either, because the HTML I am trying to render uses some CSS and Javascript resources with relative URLs, and thus I it needs a to launch with a Base URL. And as far as I know, GpmWebView doesn't support adding a base URL. (That is actually a good feature request as well).