Question

我有一个带片段的活动和一个ContentProvider。出于某种原因，我的ContentProvider的查询方法永远不会被调用 - 我已经在Eclipse调试器中验证了这一点。这是我的相关片段代码：

public class ListFrag extends ListFragment implements LoaderManager.LoaderCallbacks<Cursor> {
private SimpleCursorAdapter mAdapter;
@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    Intent myData = getActivity().getIntent();
    Bundle info = myData.getExtras();

    String[] dataColumns = { "stitchname" };
    int[] viewIDs = { R.id.stitchlist1 };
    mAdapter = new SimpleCursorAdapter(getActivity(), R.layout.stitchlist, null, dataColumns, viewIDs, 0);
    setListAdapter(mAdapter);
    getLoaderManager().initLoader(0, info, (LoaderCallbacks<Cursor>) this); 

}
}
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
    String selection = "stitchlevel=?";
    String[] selectionArgs = new String[] {args.getString("Level")};
    return (Loader<Cursor>) new CursorLoader(getActivity(), STITCHES_URI,
            PROJECTION, selection, selectionArgs, null);    
}

这是相关的ContentProvider查询。 SQLData是我的SQLiteDatabase：

public class StitchProvider extends ContentProvider {
private static final String STITCHTABLE_BASEPATH = "MyStitches_tbl";
public static final int STITCHES = 100;
public static final int STITCHES_ID = 110;
private SQLData mDB;
@Override
public Cursor query(Uri uri, String[] projection, String selection,
        String[] selectionArgs, String sortOrder) {
    SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
    queryBuilder.setTables(STITCHTABLE_BASEPATH);
    int uriType = sURIMatcher.match(uri);
    switch (uriType)
    {
    case STITCHES_ID:
        queryBuilder.appendWhere(SQLData.KEY_ROWID + "=" + uri.getLastPathSegment());
        break;
    case STITCHES:
        //no filter
        break;
    default:
        throw new IllegalArgumentException("Unknown URI");
    }
    Cursor cursor = queryBuilder.query(mDB.getReadableDatabase(), projection, selection, selectionArgs, null, null, sortOrder);
    cursor.setNotificationUri(getContext().getContentResolver(), uri);
    return cursor;
}
private static final UriMatcher sURIMatcher = new UriMatcher(UriMatcher.NO_MATCH);
static {    
    sURIMatcher.addURI(AUTHORITY, STITCHTABLE_BASEPATH, STITCHES);    
    sURIMatcher.addURI(AUTHORITY, STITCHTABLE_BASEPATH + "/#", STITCHES_ID);
    }
}

关于为什么从未调用此查询方法的任何想法？谢谢！

Answer 1

正如@nandeesh在评论中提到的那样，通过在清单文件中声明您的提供程序来解决此问题。

它应该在表格上：

<manifest>
    ...
    <application>
        <activity>...</activity>

    ...
    <provider ... />

    </application>
</manifest>

我能够在我的项目中重现这个问题。我希望它可以被检测为某种警告。但是如果有人遇到没有调用查询，在我的情况下并不是所有的ContentProvider接口方法都被调用过，这是因为我还没有在Manifest文件中声明提供者。

我希望将来很好地帮助其他人。

正在调用ContentProvider的查询方法

1 个答案: