Android : Passing value from helper thread to main thread

I have a thread with a try-catch block. Inside the try block I have the HTML stored in a variable which I want to load into a webview. Now Android/Java doesn't allow Webview to be called any other place apart from main thread.

How can I pass this String variable value outside the scope of thread? Making string variable final and declaring outside thread doesn't help.

public class MyCustomView extends LinearLayout {
//UI elements
private WebView mWebView;


new Thread(new Runnable() {

        @Override
        public void run() {
            try {

                //Using thread because accessing network
                URL obj = new URL(adrequesturl);
                HttpURLConnection con = (HttpURLConnection) obj.openConnection();
                con.setRequestMethod("GET");


                if (con.getResponseCode() == 200) {

                //*****Need this variable's value in the Main Thread
                String dataToLoad="some_custom_html";


              //mWebView is a webview that I have created and below can not get executed from inside helper thread                      
              //mWebView.loadData(dataToLoad, "text/html", "utf-8");-

                } else {
                    //Some code
                }

            } catch (Exception e) {
                    //Some code
            }
        }

    }).start();


  //Now we are back to main thread

  //********Main Problem**************
  //Below mWebView.loadData is allowed but I can not get dataToLoad value here
  mWebView.loadData(dataToLoad, "text/html", "utf-8");

}