删除单个 SQLite 行

Question

我正在尝试使用列表项的 onLongClick 删除单行，但有时它会删除该行，有时不会。也许我向它传递了错误的 ID，我没有得到真正的问题所在。

我已经尝试了一些代码，我从过去 2 天开始尝试，但无法解决这个问题。

下面是我的代码。

@Override
    public boolean onItemLongClick(AdapterView<?> parent, View view, final int position, final long id) {
        AlertDialog.Builder alert = new AlertDialog.Builder(FavouriteListActivity.this);
        alert.setMessage("Do you want to unfavorite selected item ?");
        alert.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                Log.i("===========", "Position === " + position);
                Log.i("===========", "long id === " + id);
                deleteMethod(id);
                showFavouriteList();
                dialog.cancel();
            }
        });
        alert.setNegativeButton("No", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.cancel();
            }
        });
        alert.show();
        return true;
    }

和删除方法

private void deleteMethod(long Id) {
        try {
            long shId = Id + 1;
            SQLiteDatabase db = OpenHelper.getDataHelper(getApplicationContext());
            String query = "DELETE FROM " + LocalDatabase.FAVORITE_LIST.TABLE_FAVOURITE_LIST + " WHERE " + LocalDatabase.FAVORITE_LIST.FAVOURITE_LIST_ID + " = " + shId;
            Log.i("QUERY", "" + query);
            db.execSQL(query);
            db.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

虽然我没有收到任何错误，但它并没有从数据库或列表视图中删除项目

Answer 1

首先在模型中创建一个 id 变量 class 并为此生成 getter 和 setter:

public static final String PRIMARY_ID="_id";

现在将 primeary_id 设置为从光标建模：

if (cursor.moveToFirst()) {
            do {
                model = new FavouriteListVo(lngID, strName);
                  model.setStrName(cursor.getString(cursor.getColumnIndex(LocalDatabase.FAVORITE_LIST.FAVOURITE_LIST_NAME)));
model.setPrimId(cursor.getString(cursor.getColumnIndex(LocalDatabase.FAVORITE_LIST.PRIMARY_ID)));
                arrayListFav.add(model);
            } while (cursor.moveToNext());
        }

现在要删除该行，请使用此主键：

 public void onClick(DialogInterface dialog, int which) {
            String id=model.getPrimId();
            deleteMethod(id);
            showFavouriteList();
            dialog.cancel();
        }

删除功能与您的完全相同，正如我在评论中提到的，问题出在 id 而不是您的删除功能：

private void deleteMethod(long Id) {
    try {
        long shId = Id + 1;
        SQLiteDatabase db = OpenHelper.getDataHelper(getApplicationContext());
        String query = "DELETE FROM " + LocalDatabase.FAVORITE_LIST.TABLE_FAVOURITE_LIST + " WHERE " + LocalDatabase.FAVORITE_LIST.FAVOURITE_LIST_ID + " = " + shId;
        Log.i("QUERY", "" + query);
        db.execSQL(query);
        db.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

删除单个 SQLite 行

Deleting a single SQLite row

sqlite

android

delete-row

sql-delete