public class MainActivity extends Activity{
  public boolean mBaiDuSDK_is_Ok = false;

  public boolean ismBaiDuSDK_is_Ok() {
    return mBaiDuSDK_is_Ok;
  }

  public void setmBaiDuSDK_is_Ok(boolean mBaiDuSDK_is_Ok) {
    this.mBaiDuSDK_is_Ok = mBaiDuSDK_is_Ok;
  } 
  
}

public class Test1Fragment extends Fragment implements OnClickListener {
  private Activity mActivity;

  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup container,
               Bundle savedInstanceState) {
    mActivity = getActivity();//在界面创建时，定义父Activity
    view = inflater.inflate(R.layout.fragment_test1, container, false);
    return view;
  }

  @Override
  public void onViewCreated(View view, Bundle savedInstanceState) {
   // fragment_test1 布局中的一个测试按钮
   Button test_button= (Button) view.findViewById(R.id. test_button);
   test_button setOnClickListener(this);//设置按钮监听事件

   super.onViewCreated(view, savedInstanceState);
  }

  @Override
  public void onClick(View view) {
    // TODO Auto-generated method stub
    switch (view.getId()) {
      //测试按钮监听事件
      case R.id.test_button:
        // mActivity即为代表的父Activity
        Intent intent = new Intent(mActivity, SecondActivity.class);
        Log.i("BAIDUSDK", "验证：" + ((MainActivity) mActivity).ismBaiDuSDK_is_Ok());
        //最为关键的一步，fragment调用父activity的成员方法，进行通信
        if (((MainActivity) mActivity).ismBaiDuSDK_is_Ok()) {
          startActivity(intent);
        } else {
          Log.e("TEST","请确认mBaiDuSDK_is_Ok是否正常！");
        }
      break;
    }
  }
}