title: accessing download directory as parameter in the loadUrl()
body: <p>I have built a small app to render the pdf file (e.g. income_tax_return.pdf) with the PDF.js which works fine. The PDF file is inside the assests direcotry of the Android project as well as the viewer.html. Now I am trying to load the PDF from the download directory of my Andriod device and adding it as a String to the
  <code>?file</code> attribute in the loadUrl() method.</p>
  
  <p>How can I add the path to the file attribute in the loadUrl() to render the PDF?</p>
  
  <pre><code>@Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
  
      mWebView = (WebView) findViewById(R.id.activity_main_webview);
  
      // Force links and redirects to open in the WebView instead of in a browser
      mWebView.setWebViewClient(new WebViewClient());
  
      // Enable Javascript
      WebSettings webSettings = mWebView.getSettings();
      webSettings.setJavaScriptEnabled(true);
  
      // Use local resource
      Uri path = Uri.parse(Environment.getExternalStorageDirectory().toString() + "/income_tax_return.pdf");
      Log.i("ABCD",Environment.getExternalStorageDirectory().toString() + "/income_tax_return.pdf"); //output: /storage/emulated/0/income_tax_return.pdf
       mWebView.loadUrl("file:///android_asset/pdfjs/web/viewer.html?file=income_tax_return.pdf");
  }
  </code></pre>
  
  <p><strong>Edit</strong></p>
  
  <p>when replacing my code with:</p>
  
  <pre><code>String path = Environment.getExternalStorageDirectory().toString() + "/Download/income_tax_return.pdf";
  mWebView.loadUrl( "file:///android_asset/pdfjs/web/viewer.html?file=" + path);
  </code></pre>
  
  <p>I am getting:</p>
  
  <pre><code>PDF.js Version 1.8.170 (build: 3ca67550 ) Missing PDF "file:///android_asset/psdfjs/web/Download/ income_tax_return.pdf"
  </code></pre>