title: closing webview in android
body: <p>I am using Twitter4j but I need to authenticate a user with oAuth. The user needs to get a pin and input it into the app. When I load a webview with the url and the user accept's to give the app privileges, they receive a pin. How would they close the webview in order to input the pin. I cant close the webview in the emulator. Below is the method in the Async class where the webview is shown after the url is retrieved.</p>
  
  <pre><code> protected void onPostExecute(String url) {
  
          WebView webview = new WebView(MainActivity.this);
          setContentView(webview);
          webview.loadUrl(url);
  
  
      }
  </code></pre>