@Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    mOnSaveInstanceStateInvoked = false;
    if (savedInstanceState == null) {
      setContentView(R.layout.activity_main);
      MapView mapView = (MapView) findViewById(R.id.mapView);

      mMapManager = MapManager.getInstance();
      mMapManager.init(this, mapView);
      myFragmentManager = MyFragmentManager.getInstance();
      myFragmentManager.init(getApplicationContext(), getSupportFragmentManager(), this);
      myFragmentManager.switchFragment(
          IntentHelper.getInstance().getSingleIntent(MainFragment.class, null));
      ServiceEngin.getInstance().init(this);
      LoginHelper.checkLogin(
          this,
          new LoginHelper.OnCheckLoginListener() {
            @Override
            public void onAgree() {
              myFragmentManager.showFragment(
                  IntentHelper.getInstance().getSingleIntent(LoginFragment.class, null));
            }

            @Override
            public void onCancel() {}
          });
    }
  }
 @Override
 protected void onDestroy() {
   if (mMapManager != null) {
     mMapManager.onDestroy();
   }
   if (myFragmentManager != null) {
     myFragmentManager.onDestroy();
     myFragmentManager = null;
   }
   super.onDestroy();
 }
 @Override
 public void onBackPressed() {
   if (!ServiceEngin.getInstance().canclDialog() && myFragmentManager != null) {
     myFragmentManager.onBackPressed();
   }
 }