为什么 getLoaderManager.initLoader() 第三个参数 = 这个无效？

Question

在 Udacity ND..Pet 应用程序中，在扩展 AppCompaActivity 和实现 LoaderManager.LoaderCallbacks 的活动中调用 getLoaderManager.initLoader(0,null,this); 显示第三个参数无效的错误。//THESE ARE SOME OF THE IMPORT STATEMENTS;import android.support.v4.app.LoaderManager;    import android.support.v4.content.CursorLoader; import android.support.v4.content.Loader;       import android.support.v7.app.AppCompatActivity;public class CatalogActivity extends AppCompatActivity implements LoaderManager.LoaderCallbacks<Cursor> {/** Database helper that will provide us access to the database */private PetDbHelper mDbHelper;PetCursorAdapter mCursorAdapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_catalog);    // Setup FAB to open EditorActivity    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);    fab.setOnClickListener(new View.OnClickListener() {            @Override        public void onClick(View view) {            Intent intent = new Intent(CatalogActivity.this, EditorActivity.class);            startActivity(intent);        }    });    ListView listView = (ListView) findViewById(R.id.listview);    View emptyListView = (View) findViewById(R.id.empty_view);    listView.setEmptyView(emptyListView);    //mDbHelper = new PetDbHelper(this);    mCursorAdapter = new PetCursorAdapter(this,null);    listView.setAdapter(mCursorAdapter);    getLoaderManager().initLoader(0,null,this);<-----HERE    // To access our database, we instantiate our subclass of SQLiteOpenHelper    // and pass the context, which is the current activity.}

Answer 1

只需将您的导入替换 import android.support.v4.app.LoaderManager; 为 import android.app.LoaderManager;