java - Eclipse 无法将我的类(class)识别为 fragment

Question

我正在尝试为我的 FragmenteActivity 类实例化一个 fragment ，但 Eclipse 不允许我这样做!

让我告诉你:

那是我的 fragment 类:

public class VendorListFragment extends Fragment {

    private VendorListAdapter adapter;
    private ArrayList<Vendor> vendorList;
    private VendorSQLiteHelper dbHelper;
    private ListView listView;

    public VendorListFragment() {
        // empty constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_vendor_list, container, false);          
        listView = (ListView) rootView.findViewById(R.id.listView);
        listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE_MODAL);

        this.setRetainInstance(true);

        return rootView;
    }

所以你可以看到它扩展了 Fragment，对吧？但是在我的 FragmentActivity 类中，如上所示，当我编写代码时

fragmentTransaction.add(R.id.view_trade_show_vendor_fragment, new VendorListFragment()); 

eclipse 说:

The method add(int, Fragment) in the type FragmentTransaction is not applicable for the arguments (int, VendorListFragment)

所以，Eclipse 不认为我的 ViewTradeShowActivity 是 fragment ，即使有扩展 fragment ，有什么问题？!？

查看下面的更多代码:

public class ViewTradeShowActivity extends FragmentActivity {

    TextView viewTradeShowName;
    TradeShow tradeShow;
    Fragment vendorFragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_trade_show);

        tradeShow = getIntent().getParcelableExtra("tradeShow");

        viewTradeShowName = (TextView) findViewById(R.id.view_trade_show_name);
        viewTradeShowName.setText(tradeShow.getName());

        FragmentManager fragmentManager = getFragmentManager();
        FragmentTransaction fragmentTransaction = fragmentManager
                .beginTransaction();
        fragmentTransaction.add(R.id.view_trade_show_vendor_fragment, new VendorListFragment()); 

    }    
}

谢谢!

Answer 1

您确定导入正确吗？

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;