如何在可扩展列表视图中添加分页。如何添加加载更多按钮代码

Question

主要活动

从Sqlite＆amp; amp;获取数据的代码在可扩展列表视图中添加它。

public void getExpandableListData() {
    // Group data//
    Cursor cursor = databaseHelper.getGroupData();
    cursor.moveToFirst();
    do {
        String categoryDescription = cursor.getString(cursor    .getColumnIndex("categorydesc"));
        int categoryId = cursor.getInt(cursor.getColumnIndex("CategoryId"));
        listDataHeader.add(categoryDescription);
        // Child data//
        Cursor cursorChild = databaseHelper.getChildData(categoryId);
        List<ChildInfo> childList = new ArrayList<ChildInfo>();
        cursorChild.moveToFirst();
        while (cursorChild.moveToNext()) {
            String businessName = cursorChild.getString(cursorChild.getColumnIndex("BusinessName"));
            phoneNumber = cursorChild.getString(cursorChild.getColumnIndex("ph_Phone"));
            String landMark = cursorChild.getString(cursorChild.getColumnIndex("LandMark"));
            ChildInfo childInfo = new ChildInfo(businessName, phoneNumber,  landMark);
            childList.add(childInfo);
        }
        childDataHashMap.put(categoryDescription, childList);
        } while (cursor.moveToNext());
    cursor.close();
}

DataBaseHelper类

public Cursor getGroupData() {
    String query = "SELECT * FROM Category GROUP BY categorydesc";
    return db.rawQuery(query, null);
}

 public Cursor getChildData(int CategoryId) {
    String query = "SELECT * from Category WHERE CategoryId = '" + CategoryId + "' LIMIT 3" ;
    return db.rawQuery(query, null);
}

在加载更多选项卡上单击我必须从Sqlite数据库获取数据并将其设置为可扩展列表视图。任何人都可以建议我如何避免重复从Sqlite获取数据并保持获取数据的数量。