// we want a self defined behavior for the back button
  @Override
  public void onBackPressed() {
    // exit fullscreen mode if it is enabled and action bar is disabled or the back stack is empty
    if (mIitcWebView.isInFullscreen() && mBackStack.isEmpty()) {
      mIitcWebView.toggleFullscreen();
      return;
    }

    // close drawer if opened
    if (mNavigationHelper.isDrawerOpened()) {
      mNavigationHelper.closeDrawers();
      return;
    }

    // kill all open iitc dialogs
    if (!mDialogStack.isEmpty()) {
      final String id = mDialogStack.pop();
      mIitcWebView.loadUrl(
          "javascript: "
              + "var selector = $(window.DIALOGS['"
              + id
              + "']); "
              + "selector.dialog('close'); "
              + "selector.remove();");
      return;
    }

    // Pop last item from backstack and pretend the relevant menu item was clicked
    if (!mBackStack.isEmpty()) {
      backStackPop();
      mBackButtonPressed = true;
      return;
    }

    if (mBackButtonPressed || !mSharedPrefs.getBoolean("pref_press_twice_to_exit", false)) {
      super.onBackPressed();
    } else {
      mBackButtonPressed = true;
      Toast.makeText(this, "Press twice to exit", Toast.LENGTH_SHORT).show();
      // reset back button after 2 seconds
      new Handler()
          .postDelayed(
              new Runnable() {
                @Override
                public void run() {
                  mBackButtonPressed = false;
                }
              },
              2000);
    }
  }
  @Override
  public boolean onOptionsItemSelected(final MenuItem item) {
    if (mNavigationHelper.onOptionsItemSelected(item)) return true;

    // Handle item selection
    final int itemId = item.getItemId();

    switch (itemId) {
      case android.R.id.home:
        switchToPane(Pane.MAP);
        return true;
      case R.id.reload_button:
        reloadIITC();
        return true;
      case R.id.toggle_fullscreen:
        mIitcWebView.toggleFullscreen();
        return true;
      case R.id.layer_chooser:
        mNavigationHelper.openRightDrawer();
        return true;
      case R.id.locate: // get the users current location and focus it on map
        switchToPane(Pane.MAP);

        if (mUserLocation.hasCurrentLocation()) {
          // if gps location is displayed we can use a better location without any costs
          mUserLocation.locate(mPersistentZoom);
        } else {
          // get location from network by default
          mIitcWebView.loadUrl(
              "javascript: window.map.locate({setView : true"
                  + (mPersistentZoom ? ", maxZoom : map.getZoom()" : "")
                  + "});");
        }
        return true;
      case R.id.action_settings: // start settings activity
        final Intent intent = new Intent(this, PreferenceActivity.class);
        try {
          intent.putExtra("iitc_version", mFileManager.getIITCVersion());
        } catch (final IOException e) {
          Log.w(e);
          return true;
        }
        startActivity(intent);
        return true;
      case R.id.menu_clear_cookies:
        final CookieManager cm = CookieManager.getInstance();
        cm.removeAllCookie();
        return true;
      case R.id.menu_send_screenshot:
        sendScreenshot();
        return true;
      case R.id.menu_debug:
        mDebugging = !mDebugging;
        updateViews();
        invalidateOptionsMenu();

        // TODO remove debugging stuff from JS?
        return true;
      default:
        return false;
    }
  }