/**
     * Inject js code into a WebView from a file<br>
     * Call this method on onPageFinished.
     *
     * @param fileName <i>String</i> name of the file to read.
     * @param webView <i>WebView</i> where to inject javascript code.
     *
     */
    private void injectJSIntoWebView(String fileName, WebView webView) {

        StringBuilder contentJS = new StringBuilder();

        try {
            /* Input butter */
            InputStream in = getAssets().open(fileName);
            /* Read buffer */
            BufferedReader reader = new BufferedReader(new InputStreamReader(in));
            String line;

            /* While the read line of the reading buffer is not null */
            while ((line = reader.readLine()) != null) {
                /* Add to StringBuilder object */
                contentJS.append(line);
                /* Line break */
                contentJS.append("\n");
            }

            /* Inject javascript code into webView */
            webView.loadUrl("javascript:(" + contentJS.toString() + ")()");

            /* Close input and reading buffer */
            in.close();
            reader.close();

        } catch (IOException e) {
            e.printStackTrace();
        }
    }