How do I see request headers on Android WebView requests?

Question

How can I intercept all requests made out of an Android WebView and get the corresponding request headers? I want to see the headers for every request made from my WebView including XHRs, script sources, css, etc.

The equivalent on iOS is to override NSURLCache which will give you all this information. The following are probably the closest to what I want but as far as I can see WebViewClient only ever gives us back strings:

void onLoadResource(WebView view, String url);
WebResourceResponse shouldInterceptRequest(WebView view, String url);

Answer 1

webview.setWebViewClient(new WebViewClient() {
            @SuppressLint("NewApi")
            @Override
            public WebResourceResponse shouldInterceptRequest(WebView view, WebResourceRequest request) {
                Log.d("", "request.getRequestHeaders()::"+request.getRequestHeaders());

                return null;
            }
        });