Question

我想添加一个带有两个文本的项目列表，请帮我这个，我的数据库类是：

DBHelper.java

public class DBHelper extends SQLiteOpenHelper {
  private final static String DATABASE_NAME = "NewDBtest";
    private final static int DATABASE_VERSION = 1;
    private final static String TABLE_NAME = "table1";
    private final static String COL_ID = "id";

    private final static String COL_imei = "imei";
    private final static String COL_contact = "contactNo";
    private static final String KEY_ListItem = "listitem";

    public DBHelper(Context context) {
        //1. Initialised database
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        //2. Create table
        String createTableQuery = "CREATE TABLE " + TABLE_NAME + "(" +
                COL_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
                COL_imei + " TEXT," +
                COL_contact + " TEXT," +

                KEY_ListItem + " TEXT)";
        db.execSQL(createTableQuery);

    }
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
//
        onCreate(db);

    }

    void addListItem(ArrayList<String> listItem) {

        SQLiteDatabase db = this.getWritableDatabase();

//        ContentValues values = new ContentValues();
        for (int i = 0; i < listItem.size(); i++) {
            ContentValues values = new ContentValues();
            Log.e("vlaue inserting==", "" + listItem.get(i));
            values.put(KEY_ListItem, listItem.get(i));
            db.insert(TABLE_NAME, null, values);
        }
        db.close(); // Closing database connection
    }



    Cursor getListItem() {
        String selectQuery = "SELECT  * FROM " + TABLE_NAME;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);

        return cursor;
    }



    // ### OWN CRUD METHODS ###
    // Create / Insert


    public long insert(User user) {
        // 1. init database object
        SQLiteDatabase DataBase = this.getWritableDatabase();

        // 2. init ContentValues object
        ContentValues row = new ContentValues();

        row.put(COL_imei, user.getImeiNo());
        row.put(COL_contact, user.getContact_1());

        //3. insert row into table
        long id = DataBase.insert(TABLE_NAME, null, row);
        //4. disconnect database
        DataBase.close();
        if (id != 0) {
            return id;
        }
        return 0;
    }

    public List<User> readAll() {
        //1.Init database
        SQLiteDatabase DataBase = this.getReadableDatabase();

        //2.create query
        String selectAllQuery = "Select * from " + TABLE_NAME;

        //3. fire query and catch output into cursor object
        Cursor result = DataBase.rawQuery(selectAllQuery, null);

        // 4. Iterate through a result
        if (result != null) {
            //4.1 move pointer to first row
            boolean isFirstRow = result.moveToFirst();
            //4.2 create list of users object
            List<User> list = new ArrayList<>();

            //result.moveToFirst();
            if (isFirstRow) {
                do {
                    String idOfName = result.getString(result.getColumnIndex(COL_ID));

                    String name = result.getString(result.getColumnIndex(COL_imei));
                    String last_name = result.getString(result.getColumnIndex(COL_contact));

                    User object = new User();

                    object.setId1(idOfName);

                    object.setImeiNo(name);
                    object.setContact_1(last_name);

                    list.add(object);
                }
                while (result.moveToNext());
                return list;
            }
        }
        return null;
    }
}

所以，添加列表项是我想要存储在“插入”功能中的列表意味着当我从另一个类调用insert时它将存储文本以及列表，

Answer 1

您无法直接添加列表。你可以在循环中调用这个方法addListItem（）。

Answer 2

您无法直接在列中插入列表，但可以使用JSON，

执行此操作

请考虑以下代码以供参考，您可以根据自己的要求进行操作，

首先在JSON中转换您的列表，然后在字符串中转换

JSONObject json = new JSONObject();
json.put("listObject", new JSONArray(listItem.get(i)));
// If you have one object then use JSONObject instead of JSONArray
String arrayList = json.toString();
values.put(KEY_ListItem, arrayList);

通过这种方式，您可以插入数据

要从数据库中获取数据，请使用以下代码

JSONObject json = new JSONObject(KEY_ListItem);
ArrayList items = json.optJSONArray("listObject");

这将帮助您满足您的要求。

我想在sqlite数据库中添加带有两个文本的项目列表

2 个答案: