android - 排序顺序不适用于 listView 和游标加载器

Question

我有一个 listView，它由来自游标加载器的游标填充，并使用内容提供程序。我想对 listView 进行排序，例如将最新的项目添加到 listView 的顶部。 listView 总是以相同的顺序出现，我无法更改此顺序。

我尝试使用排序顺序并对其进行更改，无论将其设置为什么，listView 始终显示相同位置的项目。使用这样的排序顺序，

  CursorLoader loader = new CursorLoader
  (List.this, Database.CONTENT_URI, projection,
  null, null, LocationsTable.TIME_STAMP + " ASC");

除了 TIME_STAMP 之外，我尝试按其他列排序，但结果始终相同。列表中项目的顺序永远不会改变。即使将 ASC 更改为 DESC 也没有任何效果。

如何设置在填充有 cursorAdapter 的 listView 中显示的项目的顺序或位置？

来自 listview 类的更多代码示例

来自onCreate方法

    adapter = new ViewAdapter(this, null, 0);

// sets array adapter to listview
listViewOne.setAdapter(adapter);

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

LoaderCallbacks<Cursor>的三个回调方法

     @Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        String projection[] = new String[]{LocationsTable._ID,
        LocationsTable.LATITUDE, LocationsTable.LONGITUDE,
    LocationsTable.LAND_ADDRESS, LocationsTable.LAST_NAME,
        LocationsTable.FIRST_NAME, LocationsTable.LOCATION_IMAGE,
    LocationsTable.TIME_STAMP };

     CursorLoader loader = new CursorLoader
    (List.this, Database.CONTENT_URI, projection, null, null,
     LocationsTable.TIME_STAMP + " ASC");
    return loader;
} // onCreateLoader

@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
    adapter.swapCursor(cursor);
} // onLoadFinished

@Override
public void onLoaderReset(Loader<Cursor> arg0) {
     adapter.swapCursor(null);
} // onLoaderReset

这是用于在数据库中创建表的字符串 extends ContentProvider

 private static final String SQL_QUERY_CREATE = "CREATE TABLE "
+ LocationsTable.TABLE_NAME + " (" + LocationsTable._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + LocationsTable.LATITUDE + " TEXT NOT NULL, "
+ LocationsTable.LONGITUDE + " TEXT NOT NULL, " + LocationsTable.LAND_ADDRESS + " TEXT, " + LocationsTable.LAST_NAME + " TEXT, " 
+ LocationsTable.FIRST_NAME + " TEXT, " + LocationsTable.LAST_NAME_ALT + " TEXT, "  + LocationsTable.FIRST_NAME_ALT + " TEXT, " 
+ LocationsTable.CONTACT_ADDRESS + " TEXT, " + LocationsTable.PHONE_NUMBER + " TEXT, "  + LocationsTable.MOBILE_NUMBER + " TEXT, "
+ LocationsTable.EMAIL + " TEXT, " + LocationsTable.LOCATION_IMAGE + " TEXT, " + LocationsTable.TIME_STAMP_IMAGE + " INTEGER, " 
+ LocationsTable.TIME_STAMP + " INTEGER " + ");";

游标适配器类

 public class ViewAdapter extends CursorAdapter {

LayoutInflater inflater;
    LatAndLngString latAndLng;

public ViewAdapter(Context context, Cursor cursor, int b) {
    super(context, cursor, b);

    inflater = LayoutInflater.from(context);
} // ViewAdapter constructor    

@Override
public void bindView(View view, final Context context, Cursor cursor) {

    TextView textViewOne = (TextView) view.findViewById(R.id.textView1); // address
    TextView textViewTwo = (TextView) view.findViewById(R.id.textView2); // last name 
    TextView textViewThree = (TextView) view.findViewById(R.id.textView3); // first name
    final Button buttonOne = (Button) view.findViewById(R.id.button1);
    final ImageView imageViewOne = (ImageView) view.findViewById(R.id.imageView1);
    final ImageView imageViewTwo = (ImageView) view.findViewById(R.id.imageView2);
    textViewOne.setText(cursor.getString(cursor.getColumnIndex(LocationsTable.LAND_ADDRESS)));
    textViewTwo.setText(cursor.getString(cursor.getColumnIndex(LocationsTable.LAST_NAME)));
    textViewThree.setText(cursor.getString(cursor.getColumnIndex(LocationsTable.FIRST_NAME)));
    String latitude = cursor.getString(cursor.getColumnIndex(LocationsTable.LATITUDE));
    String longitude = cursor.getString(cursor.getColumnIndex(LocationsTable.LONGITUDE));
    String imagePath = cursor.getString(cursor.getColumnIndex(LocationsTable.LOCATION_IMAGE));
    long timeStampImage = cursor.getLong(cursor.getColumnIndex(LocationsTable.TIME_STAMP));

    if(imagePath != null){

        int widthInDP = (int)     TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 80, getResources().getDisplayMetrics());
        int heightInDP = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 50, getResources().getDisplayMetrics());
        Bitmap sizedBitmap = ImageUtil.createReducedBitmap(imagePath, widthInDP, heightInDP);
        imageViewTwo.setImageBitmap(sizedBitmap);
    }

       textViewOne.setMaxLines(1);
       textViewTwo.setMaxLines(2);
       textViewThree.setMaxLines(3);

    final LatAndLngString latAndLng = new LatAndLngString(latitude, longitude);

    buttonOne.setTag(latAndLng);
    imageViewOne.setTag(latAndLng);
    imageViewTwo.setTag(latAndLng);

    // go to register page to edit fields
     buttonOne.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View view, MotionEvent event) {

                     if (event.getAction() == MotionEvent.ACTION_DOWN) {

                            ((Button) view).setAlpha(0.3f);

                            LatAndLngString latAndLngRow = (LatAndLngString) buttonOne.getTag();

                            Intent intent = new Intent(List.this, Register.class);                                                      
                            intent.putExtra("latitude", String.valueOf(latAndLngRow.latitude));
                            intent.putExtra("longitude", String.valueOf(latAndLngRow.longitude));
                            intent.putExtra("origin", 1);
                            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                            List.this.startActivity(intent);

                            return true;
                        } else if (event.getAction() == MotionEvent.ACTION_UP) {

                            ((Button) view).setAlpha(1.0f);

                            return true;

                        }
                        return false;
           }                
      });           

    // go to map page to display map
     imageViewOne.setOnTouchListener(new OnTouchListener() {

            @Override
            public boolean onTouch(View view, MotionEvent event) {              

                     if (event.getAction() == MotionEvent.ACTION_DOWN) {

                            ((ImageView) view).setAlpha(0.3f);

LatAndLngString latAndLngRow = (LatAndLngString) buttonOne.getTag();

                            Intent intent = new Intent(List.this, Map.class);
                            intent.putExtra("latitude", String.valueOf(latAndLngRow.latitude));
                            intent.putExtra("longitude", String.valueOf(latAndLngRow.longitude));
                            intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);                               
                            intent.putExtra("showMarker", true);

                            List.this.startActivity(intent);

                            return true;
                        } else if (event.getAction() == MotionEvent.ACTION_UP) {

                            ((ImageView) view).setAlpha(1.0f);

                            return true;

                        }
                        return false;
            } 
        });

    // set image for button
             imageViewTwo.setOnTouchListener(new OnTouchListener() {

                    @Override
                    public boolean onTouch(View view, MotionEvent event) {

                             if (event.getAction() == MotionEvent.ACTION_DOWN) {

                                    ((ImageView) view).setAlpha(0.3f);

                                    LatAndLngString latAndLngRow = (LatAndLngString) view.getTag();

                                    Intent intent = new Intent(List.this, ImageSelector.class);                                                         
                                    intent.putExtra("latitude", String.valueOf(latAndLngRow.latitude));
                                    intent.putExtra("longitude", String.valueOf(latAndLngRow.longitude));
                                    List.this.startActivity(intent);

                                    return true;
                                } else if (event.getAction() == MotionEvent.ACTION_UP) {

                                    ((ImageView) view).setAlpha(1.0f);

                                    return true;

                                }
                                return false;
                   }                
              });       

}

@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {

    return inflater.inflate(R.layout.listview_row, parent, false);

}

} 

此处为 CONTENT PROVIDER CLASS 完整代码

 // application package name

 // import statements

 public class Database extends ContentProvider {

private static final UriMatcher sUriMatcher;

private static final int LOCATIONS_ALL = 1;
private static final int LOCATIONS_ONE = 2;

public static final String AUTHORITY = "com.xxx.realestatelocator.Locations";
public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/locations");

public static final String DATABASE_NAME = "locations.db";
public static final int DATABASE_VERSION = 1;

public static final String CONTENT_TYPE_NOTES_ALL = "vnd.android.cursor.dir/vnd.realestate.locations";
public static final String CONTENT_TYPE_NOTES_ONE = "vnd.android.cursor.item/vnd.realestate.locations";

static {
        sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
        sUriMatcher.addURI(AUTHORITY, "locations", LOCATIONS_ALL);
        sUriMatcher.addURI(AUTHORITY, "locations/#", LOCATIONS_ONE);
       }

// Map table columns
    private static final HashMap<String, String> sNotesColumnProjectionMap;

    private DatabaseHelper mDbHelper;

    static {
        sNotesColumnProjectionMap = new HashMap<String, String>();
        sNotesColumnProjectionMap.put(LocationsTable._ID, LocationsTable._ID);
        sNotesColumnProjectionMap.put(LocationsTable.LATITUDE, LocationsTable.LATITUDE);
        sNotesColumnProjectionMap.put(LocationsTable.LONGITUDE, LocationsTable.LONGITUDE);
        sNotesColumnProjectionMap.put(LocationsTable.LAND_ADDRESS, LocationsTable.LAND_ADDRESS);
        sNotesColumnProjectionMap.put(LocationsTable.LAST_NAME, LocationsTable.LAST_NAME);
        sNotesColumnProjectionMap.put(LocationsTable.FIRST_NAME, LocationsTable.FIRST_NAME);
        sNotesColumnProjectionMap.put(LocationsTable.LAST_NAME_ALT, LocationsTable.LAST_NAME_ALT);
        sNotesColumnProjectionMap.put(LocationsTable.FIRST_NAME_ALT, LocationsTable.FIRST_NAME_ALT);
        sNotesColumnProjectionMap.put(LocationsTable.CONTACT_ADDRESS, LocationsTable.CONTACT_ADDRESS);
        sNotesColumnProjectionMap.put(LocationsTable.PHONE_NUMBER, LocationsTable.PHONE_NUMBER);
        sNotesColumnProjectionMap.put(LocationsTable.MOBILE_NUMBER, LocationsTable.MOBILE_NUMBER);
        sNotesColumnProjectionMap.put(LocationsTable.EMAIL, LocationsTable.EMAIL);
        sNotesColumnProjectionMap.put(LocationsTable.LOCATION_IMAGE, LocationsTable.LOCATION_IMAGE);
        sNotesColumnProjectionMap.put(LocationsTable.TIME_STAMP_IMAGE, LocationsTable.TIME_STAMP_IMAGE);
        sNotesColumnProjectionMap.put(LocationsTable.TIME_STAMP, LocationsTable.TIME_STAMP);

        } 

 public class LocationsTable implements BaseColumns {

public static final String TABLE_NAME = "tbl_locations";
public static final String _ID = "_id";
public static final String LATITUDE = "latitude";
public static final String LONGITUDE = "longitude";
public static final String LAND_ADDRESS = "land_address";
public static final String LAST_NAME = "last_name";
public static final String FIRST_NAME = "first_name";
public static final String LAST_NAME_ALT = "last_name_alt";
    public static final String FIRST_NAME_ALT = "first_name_alt";
public static final String CONTACT_ADDRESS = "contact_address";
public static final String PHONE_NUMBER = "phone_number";
public static final String MOBILE_NUMBER = "mobile_number";
public static final String EMAIL = "email_address";
public static final String LOCATION_IMAGE = "location_image";
public static final String TIME_STAMP_IMAGE = "time_stamp_image";
public static final String TIME_STAMP = "time_stamp";

} // LocationsTable inner class

private static class DatabaseHelper extends SQLiteOpenHelper {

public DatabaseHelper(Context context) {
    super(context, DATABASE_NAME, null, DATABASE_VERSION);
}

private static final String SQL_QUERY_CREATE = "CREATE TABLE "
+ LocationsTable.TABLE_NAME + " (" + LocationsTable._ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + LocationsTable.LATITUDE + " TEXT NOT NULL, "
+ LocationsTable.LONGITUDE + " TEXT NOT NULL, " + LocationsTable.LAND_ADDRESS + " TEXT, " + LocationsTable.LAST_NAME + " TEXT, " 
+ LocationsTable.FIRST_NAME + " TEXT, " + LocationsTable.LAST_NAME_ALT + " TEXT, "  + LocationsTable.FIRST_NAME_ALT + " TEXT, " 
+ LocationsTable.CONTACT_ADDRESS + " TEXT, " + LocationsTable.PHONE_NUMBER + " TEXT, "  + LocationsTable.MOBILE_NUMBER + " TEXT, "
+ LocationsTable.EMAIL + " TEXT, " + LocationsTable.LOCATION_IMAGE + " TEXT, " + LocationsTable.TIME_STAMP_IMAGE + " INTEGER, " 
+ LocationsTable.TIME_STAMP + " INTEGER " + ");";

private static final String SQL_QUERY_DROP = "DROP TABLE IF EXISTS " + LocationsTable.TABLE_NAME + ";";

@Override
public void onCreate(SQLiteDatabase db) {
     db.execSQL(SQL_QUERY_CREATE);
} // onCreate

@Override
public void onUpgrade(SQLiteDatabase db, int oldVer, int newVer) {
    db.execSQL(SQL_QUERY_DROP);
    onCreate(db);
} // onUpgrade

} // DatabaseHelper inner class

@Override
public boolean onCreate() {
   if(mDbHelper == null) {
   mDbHelper = new DatabaseHelper(getContext());
   }
   return false;
}

@Override
   public String getType(Uri arg0) {
   return null;
} // getType

// insert one new row, full row
@Override
public Uri insert(Uri uri, ContentValues values) {
    if (sUriMatcher.match(uri) != LOCATIONS_ALL) {
       throw new IllegalArgumentException(" Unknown URI: " + uri);
}

SQLiteDatabase db = mDbHelper.getWritableDatabase();
long rowId = db.insert(LocationsTable.TABLE_NAME, null, values);
if (rowId > 0) {
    Uri notesUri = ContentUris.withAppendedId(CONTENT_URI, rowId);
    getContext().getContentResolver().notifyChange(notesUri, null);
    return notesUri;
}
throw new IllegalArgumentException("<Illegal>Unknown URI: " + uri);

} // insert

@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder builder = new SQLiteQueryBuilder();
    switch (sUriMatcher.match(uri)) {
    case LOCATIONS_ALL:
        builder.setTables(LocationsTable.TABLE_NAME);
        builder.setProjectionMap(sNotesColumnProjectionMap);
        break;

    case LOCATIONS_ONE:
        builder.setTables(LocationsTable.TABLE_NAME);
        builder.setProjectionMap(sNotesColumnProjectionMap);
        builder.appendWhere(LocationsTable._ID + " = " + uri.getLastPathSegment());
        break;

    default:
        throw new IllegalArgumentException("Unknown URI: " + uri);
}

SQLiteDatabase db = mDbHelper.getReadableDatabase();
    Cursor queryCursor = builder.query(db, projection, selection, selectionArgs, null, null, null);
    queryCursor.setNotificationUri(getContext().getContentResolver(), uri);

    return queryCursor;
} // query

@Override
    public int update(Uri uri, ContentValues values, String where, String[] whereArgs) {
    SQLiteDatabase db = mDbHelper.getWritableDatabase();
    int count = 0;
    switch (sUriMatcher.match(uri)) {
    case LOCATIONS_ALL:
        count = db.update(LocationsTable.TABLE_NAME, values, where, whereArgs);
        break;

    case LOCATIONS_ONE:
        String rowId = uri.getLastPathSegment();
        count = db.update(LocationsTable.TABLE_NAME, values, LocationsTable._ID 
                + " = " + rowId + (!TextUtils.isEmpty(where) ? " AND (" + ")" : ""), whereArgs);

    default:
        throw new IllegalArgumentException("Unknown URI: " + uri);
    }

    getContext().getContentResolver().notifyChange(uri, null);
    return count;
} // update

// delete
@Override
public int delete(Uri uri, String where, String[] whereArgs) {
    SQLiteDatabase db = mDbHelper.getWritableDatabase();
    int count = 0;
    switch (sUriMatcher.match(uri)) {
    case LOCATIONS_ALL:
        count = db.delete(LocationsTable.TABLE_NAME, where, whereArgs);
        break;

    case LOCATIONS_ONE: 
        String rowId = uri.getPathSegments().get(1);
        count = db.delete(LocationsTable.TABLE_NAME, LocationsTable._ID + " = "
        + rowId + (!TextUtils.isEmpty(where) ? " AND (" + where + ")" : ""), whereArgs);
        break;

    default:
        throw new IllegalArgumentException("Unknown URI: " + uri);
    }

    getContext().getContentResolver().notifyChange(uri, null);
    return count;
} // delete

} // Database

Answer 1

您似乎没有将排序顺序参数传递给数据库连接实例本身，因此结果没有得到排序。确保将 ContentProvider#query 方法中的所有参数委托(delegate)给 SQLiteDatabase。

因此，您的SQLiteQueryBuilder#build 方法应该如下所示:

Cursor queryCursor = builder.query(db, projection, selection, selectionArgs, null, null, sortOrder);