Custom WebViewClient with HttpUrlConnection - To add headers for every request (WebView)

Question

I have a webview to which I want to add custom headers, I want this to cater for redirects and looking at how to do it, I stumbled at the highest voted answer here.

However this solution is using a now deprecated approach. I tried to modify the solution:

 public void webViewUrlConn() {
        new Thread(new Runnable() {

            @Override
            public void run() {

                try {
                    URL url = new URL("https://someUrl.com");

                    HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();


                    CookieManager cookieManager = CookieManager.getInstance();
                    String cookie = cookieManager.getCookie(url.getHost());
                    urlConnection.setDoOutput(true);
                    urlConnection.setRequestProperty("Cookie", cookie);
                    urlConnection.setRequestProperty("CRM_USER_AGENT", "crm_app");
                    urlConnection.setRequestMethod("POST");

                    InputStream in = new BufferedInputStream(urlConnection.getInputStream());


                    data = new java.util.Scanner(in).useDelimiter("\\A").next();

                    System.out.println("Data:" + data);

                    urlConnection.disconnect();
                } catch (Exception e) {
                    e.printStackTrace();
                }

                getActivity().runOnUiThread(new Runnable() {
                    public void run() {
                        wv.loadData(data, "text/html", "UTF-8");
                        pd.setVisibility(View.INVISIBLE);
                        wv.setVisibility(View.VISIBLE);

                    }
                });


            }
        }).start();
    }

This works flawless. But this is not what I need. I wanted to override the WebViewClient class to cater for even the links clicked on the webview, I came up with the following:

 WebViewClient webViewClient = new WebViewClient() {

            @Override
            public WebResourceResponse shouldInterceptRequest(WebView view, String url1) {

                try {
                    URL url = new URL(url1);

                    HttpsURLConnection urlConnection = (HttpsURLConnection) url.openConnection();


                    CookieManager cookieManager = CookieManager.getInstance();
                    String cookie = cookieManager.getCookie(url.getHost());
                    urlConnection.setDoOutput(true);
                    urlConnection.setRequestProperty("Cookie", cookie);
                    urlConnection.setRequestProperty("CRM_USER_AGENT", "crm_app");
                    urlConnection.setRequestMethod("POST");

                    InputStream in = new BufferedInputStream(urlConnection.getInputStream());


                    data = new java.util.Scanner(in).useDelimiter("\\A").next();

                    System.out.println("Data:" + data);


                    urlConnection.getContentType();
                    urlConnection.getContentEncoding();
                    urlConnection.getContentEncoding();

                    urlConnection.disconnect();



                    return new WebResourceResponse("text/html","UTF-8", in);

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

                    return null;
                }


            }
        };


        wv.setWebViewClient(webViewClient);

        pd.setVisibility(View.INVISIBLE);
        wv.setVisibility(View.VISIBLE);
        wv.loadUrl("https://someurl.com");

The above does not work and I cannot establish why - I get a blank webview. and when I print the value from data I get some unknown characters.

*I get a blank webview.* because Scanner consume the stream *and when I print the value from data* maybe server is using compression ... — Selvin, Jan 22 '16 at 11:12
I will check with commenting scanner, I was not aware of it `consuming` data and that making my `in` variable unusable. As far as compression is concerned, I think that should have been the case for the other code sample too, but that works flawless. — User3, Jan 22 '16 at 11:14

score 0 · Answer 1 · edited Jun 20 '20 at 09:12

0

I am also trying to add custom headers to Webview requests, which is why I stumbled across your question. I found another question adressing a similar issue with an answer that worked for me, so it probably will do the trick for you as well:

I had the same issue. If you remove the

urlConnection.disconnect();

it works.

edited Jun 20 '20 at 09:12

Community

1
1

answered Nov 17 '16 at 16:48

Petzy Bär

135
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Custom WebViewClient with HttpUrlConnection - To add headers for every request (WebView)

1 Answers1