How to used in pdf-generator plugin

Due to some problem I need to use the "https://github.com/ionic-team/cordova-plugin-ionic-webview" plugin, so the whole url is changed. I have tried with many url format, but it is not a valid path.

as per their documentation
iOS: www/<css-folder>/<your-file.css>

Can you please tell me the solution

I tried like below
ionic://localhost/_app_file_/www/pdf.png