android - 我怎样才能得到 getLoaderManager().restartLoader(0, null, this) 得到正确的这个？

Question

当我检索我的联系人时，我试图在我的 listfragment 的 actionBar 中实现一个搜索 View 。

当我尝试使用时我的问题来了

getLoaderManager().restartLoader(0, null, this); 

在 onQueryTextChange 方法中:

我进入“this”，下一个错误:

Found: 'android.support.v7.widget.SearchView.OnQueryTextListener', required: 'android.support.v4.app.LoaderManager.LoaderCallbacks<java.lang.Object>

我不明白为什么在 onActivityCreated 方法中我可以使用相同的代码并工作:

  getLoaderManager().initLoader(0, null, this);

提前致谢!

这是我的全部代码:

import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.support.v4.app.ListFragment;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.support.v4.view.MenuItemCompat;
import android.support.v4.widget.ResourceCursorAdapter;
import android.support.v7.widget.SearchView;
import android.text.TextUtils;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Filterable;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import java.io.InputStream;


public class contacts extends ListFragment implements LoaderManager.LoaderCallbacks<Cursor>  {

    private static final String[] PROJECTION = {
        ContactsContract.Contacts._ID,
        ContactsContract.Contacts.DISPLAY_NAME,
        ContactsContract.Contacts.CONTACT_STATUS,
        ContactsContract.Contacts.CONTACT_PRESENCE,
        ContactsContract.Contacts.PHOTO_ID,
        ContactsContract.Contacts.LOOKUP_KEY,
        ContactsContract.Contacts.HAS_PHONE_NUMBER,
    };

    private MyCursorAdapter mCursorAdapter;
    private Uri baseUri;

    String cursorFilter;

    public contacts() {
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);
    }


    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        setEmptyText(getResources().getString(R.string.empty_numbers));
        mCursorAdapter  = new MyCursorAdapter(getActivity(), R.layout.list_item, null, 0 );
        setListAdapter(mCursorAdapter);
        getLoaderManager().initLoader(0, null, this);
    }

    @Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        if (cursorFilter != null) {
            baseUri = Uri.withAppendedPath(ContactsContract.Contacts.CONTENT_FILTER_URI, Uri.encode(cursorFilter));
        } else {
            baseUri = ContactsContract.Contacts.CONTENT_URI;
        }

        String select = "((" + ContactsContract.Contacts.DISPLAY_NAME + " NOTNULL) AND (" + ContactsContract.Contacts.DISPLAY_NAME + " != '' ))";
        return new CursorLoader(getActivity(), baseUri, PROJECTION, select, null, ContactsContract.Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC");
    }

    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
        mCursorAdapter.swapCursor(data);
    }

    @Override
    public void onLoaderReset(Loader<Cursor> loader) {
        mCursorAdapter.swapCursor(null);
    }

    @Override
    public void onListItemClick(ListView l, View v, int position, long id) {
        Cursor cursor = (Cursor) mCursorAdapter.getItem(position);
        String contactId = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID));
        Intent intent = new Intent(Intent.ACTION_VIEW);
        Uri uri = Uri.withAppendedPath(ContactsContract.Contacts.CONTENT_URI, contactId);
        intent.setData(uri);
        getActivity().startActivity(intent);
    }

    @Override
    public void onCreateOptionsMenu (Menu menu, MenuInflater inflater) {
        inflater.inflate(R.menu.menu_search, menu);
        MenuItem item = menu.findItem(R.id.action_search);
        final SearchView sv = new SearchView(((MainActivity) getActivity()).getSupportActionBar().getThemedContext());
        MenuItemCompat.setShowAsAction(item, MenuItemCompat.SHOW_AS_ACTION_COLLAPSE_ACTION_VIEW | MenuItemCompat.SHOW_AS_ACTION_IF_ROOM);
        MenuItemCompat.setActionView(item, sv);

        sv.setQueryHint(getString(R.string.type_search));
        sv.setIconifiedByDefault(false);
        sv.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                Toast.makeText(getActivity(), "Submitted: "+query, Toast.LENGTH_SHORT).show();
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {
                Toast.makeText(getActivity(), "tap: "+newText, Toast.LENGTH_SHORT).show();
                cursorFilter = !TextUtils.isEmpty(newText) ? newText : null;
                getLoaderManager().restartLoader(0, null, this);
                return false;
            }
        });

        MenuItemCompat.setOnActionExpandListener(item, new MenuItemCompat.OnActionExpandListener() {
            @Override
            public boolean onMenuItemActionCollapse(MenuItem item) {
                InputMethodManager mgr = (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
                mgr.hideSoftInputFromWindow(sv.getWindowToken(), 0);
                return true;
            }

            @Override
            public boolean onMenuItemActionExpand(MenuItem item) {
                sv.requestFocus();

                InputMethodManager mgr = (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
                mgr.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);

                return true;
            }
        });

        super.onCreateOptionsMenu(menu,inflater);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_search:

                break;
        }
        return true;

    }
}

Answer 1

使用contacts.this

顺便说一下，让你的类名大写。所以它应该是 Contacts.this