完成page control，完成数据的翻页功能

applications/emsConfigurer/datafetcher.cpp

@@ -13,9 +13,9 @@ DataFetcher::~DataFetcher()
 
 }
 
-bool DataFetcher::Fetch(TableData& tbl_data)
+bool DataFetcher::Fetch(TableData& tbl_data,int fetch_rows)
 {
-    int rows = MysqlUtils::getInstance()->RetrieveTableData(tbl_data);
+    int rows = MysqlUtils::getInstance()->RetrieveTableData(tbl_data,fetch_rows);
     if (rows < 0)
     {
         hloge("Failed to retrieve signal data");

applications/emsConfigurer/datafetcher.h

@@ -12,7 +12,7 @@ public:
     virtual ~DataFetcher();
 
 public:
-    virtual bool Fetch(TableData& tbl_data);
+    virtual bool Fetch(TableData& tbl_data,int fetch_rows = 1000);
 
 protected:
     int VerifyStatus();

applications/emsConfigurer/devicepropertypage.cpp

@@ -12,6 +12,9 @@
 #include "globalparameters.h"
 #include "mytablemodel.h"
 
+#define PAGES_FORMAT_STRING ("Total %1 Pages, Current No.%2 Page")
+#define PER_PAGE_SIZE (30)
+
 DevicePropertyPage::DevicePropertyPage(QWidget *parent) :
     QWidget(parent),m_pTableView(nullptr),m_pButton(nullptr)
 {
@@ -113,6 +116,22 @@ void DevicePropertyPage::InitializeTable()
     m_pTableView = new QTableView(this);
     m_pButton = new QPushButton(tr("Refresh"), this);
 
+    m_pFirstButton = new QPushButton(tr("First"), this);
+    m_pForwardButton = new QPushButton(tr("Forward"), this);
+    m_pNextButton = new QPushButton(tr("Next"), this);
+    m_pLastButton = new QPushButton(tr("Last"), this);
+
+    m_pGotoPageNumberLineEdit = new QLineEdit(tr("1"), this);
+    m_pGotoPageNumberLineEdit->setFixedWidth(40);
+    m_pValidator = new QIntValidator(this);
+    m_pGotoPageNumberLineEdit->setValidator(m_pValidator);
+    m_pValidator->setRange(0, 100);
+
+    m_pGotoPageNumberLabel = new QLabel(tr("Page"), this);
+    m_pGotoPageNumberButton = new QPushButton(tr("Goto"), this);
+
+    m_pPagesLabel = new QLabel(tr("Total %d Pages, Current No.%d Page"), this);
+
     // 创建主布局
     QVBoxLayout *mainLayout = new QVBoxLayout(this);
 
@@ -123,7 +142,26 @@ void DevicePropertyPage::InitializeTable()
     // 创建一个水平布局来包含按钮
     QHBoxLayout *buttonLayout = new QHBoxLayout();
     buttonLayout->addStretch();  // 让按钮保持在右侧
+
+    buttonLayout->addWidget(m_pPagesLabel);
+    QSpacerItem *spacer0 = new QSpacerItem(10, 20, QSizePolicy::Expanding, QSizePolicy::Minimum);
+    buttonLayout->addItem(spacer0);
+
+
+    buttonLayout->addWidget(m_pFirstButton);
+    buttonLayout->addWidget(m_pForwardButton);
+    buttonLayout->addWidget(m_pNextButton);
+    buttonLayout->addWidget(m_pLastButton);
+
+    QSpacerItem *spacer = new QSpacerItem(10, 20, QSizePolicy::Expanding, QSizePolicy::Minimum);
+    buttonLayout->addItem(spacer);
+
+    buttonLayout->addWidget(m_pGotoPageNumberLabel);
+    buttonLayout->addWidget(m_pGotoPageNumberLineEdit);
+    buttonLayout->addWidget(m_pGotoPageNumberButton);
+
     buttonLayout->addWidget(m_pButton);
+
     buttonLayout->setContentsMargins(0, 0, 0, 0);  // 取消按钮的边距
 
     // 将表格视图和按钮布局添加到主布局
@@ -139,18 +177,13 @@ void DevicePropertyPage::InitializeTable()
     connect(m_pTableView, &QTableView::doubleClicked, this, &DevicePropertyPage::onTableViewDoubleClicked);
     connect(m_pButton, &QPushButton::clicked, this, &DevicePropertyPage::onButtonClicked);
 
-    setLayout(mainLayout);
+    connect(m_pFirstButton, &QPushButton::clicked, this, &DevicePropertyPage::onFirstButtonClicked);
-}
+    connect(m_pLastButton, &QPushButton::clicked, this, &DevicePropertyPage::onLastButtonClicked);
+    connect(m_pForwardButton, &QPushButton::clicked, this, &DevicePropertyPage::onForwardButtonClicked);
+    connect(m_pNextButton, &QPushButton::clicked, this, &DevicePropertyPage::onNextButtonClicked);
+    connect(m_pGotoPageNumberButton, &QPushButton::clicked, this, &DevicePropertyPage::onGotoButtonClicked);
 
-void DevicePropertyPage::Refresh()
+    setLayout(mainLayout);
-{
-    QGuiApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
-    TableData tbl_data;
-    if (Fetch(tbl_data))
-    {
-        m_myModel->setModelData(tbl_data);
-    }
-    QGuiApplication::restoreOverrideCursor();
 }
 
 void DevicePropertyPage::setBaseType(unsigned int base, unsigned int mask)
@@ -159,7 +192,6 @@ void DevicePropertyPage::setBaseType(unsigned int base, unsigned int mask)
     mask_code = mask;
 }
 
-
 void DevicePropertyPage::onButtonClicked()
 {
     m_pTimer->stop();
@@ -167,6 +199,86 @@ void DevicePropertyPage::onButtonClicked()
     Refresh();
 }
 
+void DevicePropertyPage::Refresh()
+{
+    QGuiApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
+    m_TotalTableData.clear();
+    if (Fetch(m_TotalTableData,106))
+    {
+        PageDataProcess();
+        m_myModel->setModelData(m_currentPageData);
+    }
+    updatePageButtonState();
+    updatePageLabel();
+    QGuiApplication::restoreOverrideCursor();
+}
+
+int DevicePropertyPage::PageDataProcess()
+{
+    //获取数据总数
+    m_totalRows = m_TotalTableData.size();
+
+    m_totalPageCount = 1;
+    m_currentPage = 1;
+
+    m_currentPageData.clear();
+
+    if (m_totalRows <= PER_PAGE_SIZE)
+    {
+        m_currentPageData = m_TotalTableData;
+
+        return 1;
+    }
+
+    m_totalPageCount = int(m_totalRows / PER_PAGE_SIZE) + 1;
+    m_currentPageData = m_TotalTableData.mid(0, PER_PAGE_SIZE);
+
+    return 1;
+}
+
+void DevicePropertyPage::updatePageLabel()
+{
+    QString s = QString(PAGES_FORMAT_STRING).arg(m_totalPageCount).arg(m_currentPage);
+    m_pPagesLabel->setText(s);
+}
+
+void DevicePropertyPage::updatePageButtonState()
+{
+    if ( m_currentPage == m_totalPageCount) //翻到底了，超过最大的页数
+    {
+        m_pNextButton->setEnabled(false);
+        m_pForwardButton->setEnabled(true);
+        m_pLastButton->setEnabled(false);
+        m_pFirstButton->setEnabled(true);
+    }
+    else if (m_currentPage == 1) //翻到头了
+    {
+        m_pNextButton->setEnabled(true);
+        m_pForwardButton->setEnabled(false);
+        m_pLastButton->setEnabled(true);
+        m_pFirstButton->setEnabled(false);
+    }
+    else if (m_currentPage < m_totalPageCount) //页数在中间状态
+    {
+        m_pNextButton->setEnabled(true);
+        m_pForwardButton->setEnabled(true);
+        m_pLastButton->setEnabled(true);
+        m_pFirstButton->setEnabled(true);
+    }
+    else
+    {
+        assert(false);
+    }
+}
+
+void DevicePropertyPage::pageTo(int page)
+{
+    m_currentPageData.clear();
+    int numLeftElements = m_totalRows - (page - 1) * PER_PAGE_SIZE;
+    int numElements = numLeftElements >= PER_PAGE_SIZE ? PER_PAGE_SIZE : numLeftElements;
+    m_currentPageData = m_TotalTableData.mid((page-1) * PER_PAGE_SIZE, numElements);
+    m_myModel->setModelData(m_currentPageData);
+}
 
 void DevicePropertyPage::onTableViewDoubleClicked(const QModelIndex &index)
 {
@@ -176,6 +288,75 @@ void DevicePropertyPage::onTableViewDoubleClicked(const QModelIndex &index)
     QVariant datatemp=model->data(mindex);
 }
 
+void DevicePropertyPage::onFirstButtonClicked()
+{
+    m_currentPage = 1;
+
+    updatePageButtonState();
+
+    pageTo(m_currentPage);
+
+    updatePageLabel();
+}
+
+void DevicePropertyPage::onLastButtonClicked()
+{
+    m_currentPage = m_totalPageCount;
+
+    updatePageButtonState();
+
+    pageTo(m_currentPage);
+
+    updatePageLabel();
+}
+
+void DevicePropertyPage::onForwardButtonClicked()
+{
+    m_currentPage--;
+
+    updatePageButtonState();
+
+    m_currentPageData.clear();
+
+    pageTo(m_currentPage);
+
+    updatePageLabel();
+}
+
+void DevicePropertyPage::onNextButtonClicked()
+{
+    m_currentPage++;
+
+    updatePageButtonState();
+
+    m_currentPageData.clear();
+
+    pageTo(m_currentPage);
+
+    updatePageLabel();
+}
+
+void DevicePropertyPage::onGotoButtonClicked()
+{
+    int page = m_pGotoPageNumberLineEdit->text().toInt();
+    if (page <=0 || page>m_totalPageCount)
+    {
+        QString s = QString(tr("Page number should be large than 0 and less than %1 !")).arg(m_totalPageCount);
+        QMessageBox::critical(this, tr("Critical Message"),s);
+        return ;
+    }
+
+    m_currentPage = page;
+
+    updatePageButtonState();
+
+    m_currentPageData.clear();
+
+    pageTo(m_currentPage);
+
+    updatePageLabel();
+}
+
 void DevicePropertyPage::resizeEvent(QResizeEvent *event)
 {
     QWidget::resizeEvent(event);

applications/emsConfigurer/devicepropertypage.h

@@ -4,6 +4,10 @@
 #pragma execution_character_set("utf-8")
 
 #include <QWidget>
+#include <QLineEdit>
+#include <QLabel>
+#include <QIntValidator>
+
 #include "datafetcher.h"
 
 class MyTableModel;
@@ -37,18 +41,55 @@ protected:
     // 重写resizeEvent，当QTableView窗口大小变化时按比例调整列宽
     void resizeEvent(QResizeEvent *event) override;
 
+    //处理分页数据
+    int PageDataProcess();
+
+    //更新页数显示
+    void updatePageLabel();
+
+    //更新翻页按钮状态
+    void updatePageButtonState();
+
+    //翻倒第i页
+    void pageTo(int page);
+
 private slots:
     void onButtonClicked();
 
     void onTableViewDoubleClicked(const QModelIndex &index);
 
+    void onFirstButtonClicked();
+    void onLastButtonClicked();
+    void onForwardButtonClicked();
+    void onNextButtonClicked();
+    void onGotoButtonClicked();
 
 private:
     unsigned int filterBaseType;
     unsigned int mask_code;
     QTableView* m_pTableView;
     QPushButton* m_pButton;
+
+    QPushButton* m_pForwardButton;
+    QPushButton* m_pNextButton;
+    QPushButton* m_pFirstButton;
+    QPushButton* m_pLastButton;
+
+    QIntValidator* m_pValidator;
+    QLabel* m_pGotoPageNumberLabel;
+    QLineEdit* m_pGotoPageNumberLineEdit;
+    QPushButton* m_pGotoPageNumberButton;
+
+    QLabel* m_pPagesLabel;
+
     QVector<int> columnWidths;  // 存储初始列宽
+private:
+    TableData m_TotalTableData;
+    TableData m_currentPageData;
+
+    int m_totalPageCount;   //总页数
+    int m_currentPage;      //当前页
+    int m_totalRows;        //数据总行数
 };
 
 #endif // DEVICEPROPERTYPAGE_H

applications/emsConfigurer/formserialportsettingdialog.cpp

@@ -1,4 +1,4 @@
-#include "formserialportsettingdialog.h"
+#include "formserialportsettingdialog.h"
 #include "ui_formserialportsettingdialog.h"
 
 #include <QListView>

applications/emsConfigurer/globalparameters.cpp

@@ -136,8 +136,10 @@ AppTcpClient::AppTcpClient(token)
 {
 }
 
-void onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf);
+void onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf)
-
+{
+    hlogd("TCP Client<==\n%s", Kutilities::printHex((void*)buf->data(),(int)buf->size()).c_str());
+}
 
 int AppTcpClient::Initialize(QString remote_host, int remote_port)
 {
@@ -152,18 +154,14 @@ int AppTcpClient::Initialize(QString remote_host, int remote_port)
         }
 
         m_tcpclient = new hv::TcpClient();
+
         m_connfd = m_tcpclient->createsocket(remote_port, remote_host.toStdString().c_str());
         if (m_connfd < 0)
         {
             return -20;
         }
 
-        m_tcpclient->onMessage = onMessage;
+        //m_tcpclient->onMessage = onMessage;
-
-        //m_tcpclient.onMessage = [](const SocketChannelPtr& channel, Buffer* buf)
-        //{
-        //    hlogi("<==\n%s", Kutilities::printHex((void*)buf->data(),(int)buf->size()).c_str());
-        //};
 
         reconn_setting_t reconn;
         reconn_setting_init(&reconn);
@@ -178,7 +176,8 @@ int AppTcpClient::Initialize(QString remote_host, int remote_port)
     return m_connfd;
 }
 
-void onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf)
+void AppTcpClient::resetOnMessageCallbackFunction(onMessageCallbackFunc &func)
 {
-    hlogi("<==\n%s", Kutilities::printHex((void*)buf->data(),(int)buf->size()).c_str());
+    m_tcpclient->onMessage = func;
 }
+

applications/emsConfigurer/globalparameters.h

@@ -134,6 +134,7 @@ public:
     void InitializeTableView(MyTableModel* model,QTableView* tableView);
 };
 
+typedef std::function<void(const hv::SocketChannelPtr&, hv::Buffer*)> onMessageCallbackFunc;
 
 class AppTcpClient:public Singleton<AppTcpClient>
 {
@@ -144,7 +145,8 @@ public:
     AppTcpClient(const AppTcpClient&)=delete;
     AppTcpClient& operator =(const AppTcpClient&)= delete;
 
-    int Initialize(QString remote_host, int remote_port=DEVICE_SERVER_PORT);
+    int Initialize(QString remote_host,int remote_port=DEVICE_SERVER_PORT);
+    void resetOnMessageCallbackFunction(onMessageCallbackFunc& func);
 
 public:
     hv::TcpClient* m_tcpclient;

applications/emsConfigurer/hv_tcpclient.h

@@ -226,14 +226,17 @@ public:
 
     bool isConnected()
     {
-        if (channel == NULL) return false;
+        if (channel == NULL)
+            return false;
         return channel->isConnected();
     }
 
     // send thread-safe
     int send(const void* data, int size)
     {
-        if (!isConnected()) return -1;
+        if (!isConnected())
+            return -1;
+
         return channel->write(data, size);
     }
     int send(Buffer* buf)

applications/emsConfigurer/kutilities.cpp

@@ -1,4 +1,4 @@
-#include "kutilities.h"
+#include "kutilities.h"
 #include <iomanip>
 #include <string>
 #include <sstream>

applications/emsConfigurer/maindialog.cpp

@@ -14,6 +14,9 @@
 #include <QTableView>
 #include <QStandardItemModel>
 
+#include <hv/hlog.h>
+
+#include "kutilities.h"
 #include "devicepropertypage.h"
 #include "formserialportsettingdialog.h"
 
@@ -29,6 +32,10 @@ MainDialog::MainDialog(QWidget *parent) :
 
     // Load the window state
     loadWindowState();
+
+    //设置返回消息回调
+    onMessageCallbackFunc f = std::bind(&MainDialog::onMessage, this, std::placeholders::_1, std::placeholders::_2);
+    AppTcpClient::getInstance()->resetOnMessageCallbackFunction(f);
 }
 
 MainDialog::~MainDialog()
@@ -240,3 +247,8 @@ void MainDialog::onToolRefreshClicked()
 {
     QMessageBox::information(this, "Refresh Button Clicked", "Refresh");
 }
+
+void MainDialog::onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf)
+{
+    hlogd("MainDialog <==\n%s", Kutilities::printHex((void*)buf->data(),(int)buf->size()).c_str());
+}

applications/emsConfigurer/maindialog.h

@@ -8,6 +8,7 @@
 #include <QIcon>
 #include <QStackedWidget>
 #include <QToolBar>
+#include <hv_tcpclient.h>
 
 namespace Ui
 {
@@ -29,6 +30,8 @@ public:
 public slots:
     void changePage(QListWidgetItem *current, QListWidgetItem *previous);
 
+    //接收服务器返回消息的函数
+    void onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf);
 
 private slots:
     void onToolButton1Clicked();

applications/emsConfigurer/mainwindow.cpp

@@ -8,7 +8,7 @@
 #include <hv/hlog.h>
 #include "MainDialog.h"
 #include "mysqlutils.h"
-
+#include "kutilities.h"
 
 MainWindow::MainWindow(QWidget *parent)
     : QMainWindow(parent)
@@ -69,24 +69,37 @@ bool MainWindow::testDatabase()
     return true;
 }
 
+void MainWindow::onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf)
+{
+    hlogd("MainWindow<==\n%s", Kutilities::printHex((void*)buf->data(),(int)buf->size()).c_str());
+}
+
 bool MainWindow::testServerEcho()
 {
     using namespace hv;
 
     QString svr = ui->serverIp->text();
 
-    int connfd = AppTcpClient::getInstance()->Initialize("127.0.0.1",DEVICE_SERVER_PORT);
+    int connfd = AppTcpClient::getInstance()->Initialize(svr,DEVICE_SERVER_PORT);
     if (connfd <= 0)
     {
-        hloge("failed to connect to device data service ...");
+        hloge("failed to create socket for connecting to device data service ...");
         return false;
     }
 
-    hlogi("connect to device data service port %d, connfd=%d ...", DEVICE_SERVER_PORT, connfd);
+    hlogi("create socket for connecting to device data service port %d, connfd=%d ...", DEVICE_SERVER_PORT, connfd);
+
+    CWaitorCursor wait1;
+
+    hv_msleep(500);
+
+    //设置返回消息回调
+    onMessageCallbackFunc f = std::bind(&MainWindow::onMessage, this, std::placeholders::_1, std::placeholders::_2);
+    AppTcpClient::getInstance()->resetOnMessageCallbackFunction(f);
 
     unsigned char frame[10] = { 0x02, 0x01,0x00,0x00,0x00, 0x00,0xEE,0xFF,0xEE,0xFF};
     int cnt = AppTcpClient::getInstance()->m_tcpclient->send((void*)frame,10);
-    hlogd("send %d bytes, connfd=%d ...", cnt, connfd);
+    hlogd("send %d bytes test echo signal, connfd=%d ...", cnt, connfd);
 
     return cnt > 0 ? true : false;
 }

applications/emsConfigurer/mainwindow.h

@@ -3,6 +3,7 @@
 #pragma execution_character_set("utf-8")
 
 #include <QMainWindow>
+#include <hv_tcpclient.h>
 
 class MainDialog;
 
@@ -21,6 +22,9 @@ public:
     MainWindow(QWidget *parent = nullptr);
     ~MainWindow();
 
+public:
+    void onMessage(const hv::SocketChannelPtr& channel, hv::Buffer* buf);
+
 protected:
     void setIp(const QString &ip);
     bool testDatabase();

applications/emsConfigurer/mainwindow.ui

@@ -39,17 +39,16 @@
    <widget class="QLabel" name="label">
     <property name="geometry">
      <rect>
-      <x>160</x>
+      <x>100</x>
       <y>50</y>
-      <width>240</width>
+      <width>391</width>
       <height>61</height>
      </rect>
     </property>
     <property name="font">
      <font>
-      <family>宋体</family>
+      <pointsize>28</pointsize>
-      <italic>false</italic>
+      <bold>true</bold>
-      <bold>false</bold>
      </font>
     </property>
     <property name="text">
@@ -83,9 +82,8 @@
     </property>
     <property name="font">
      <font>
-      <family>宋体</family>
+      <pointsize>12</pointsize>
-      <italic>false</italic>
+      <bold>true</bold>
-      <bold>false</bold>
      </font>
     </property>
     <property name="text">

applications/emsConfigurer/mysqlutils.cpp

@@ -1,4 +1,4 @@
-#include "mysqlutils.h"
+#include "mysqlutils.h"
 #include <QDebug>
 
 #include <hv/hlog.h>
@@ -148,13 +148,15 @@ void MysqlUtils::CloseDatabase()
 #endif
 }
 
-int MysqlUtils::RetrieveTableData(TableData& tbl_data)
+int MysqlUtils::RetrieveTableData(TableData& tbl_data,int retrieve_rows)
 {
 #if 1
     MYSQL_RES* res;
     MYSQL_ROW row;
     //执行SQL 查询
-    if (mysql_query(m_DbConnection, "SELECT * FROM `hjems`.`tbl_data` ORDER BY data_timestamp LIMIT 0,100"))
+    QString sql = QString("SELECT * FROM `hjems`.`tbl_data` ORDER BY data_timestamp LIMIT 0,%1").arg(retrieve_rows);
+
+    if (mysql_query(m_DbConnection, sql.toStdString().c_str()))
     {
         hloge( "Error: %s", mysql_error(m_DbConnection) ) ;
         return -1;
@@ -162,33 +164,35 @@ int MysqlUtils::RetrieveTableData(TableData& tbl_data)
 
     res = mysql_use_result(m_DbConnection);
 
+    int j = 0;
     while ((row = mysql_fetch_row(res)) != NULL)
     {
+
         ModelItem item;
-        // item.status = STATUS_WARN;
+        item.status = STATUS_WARN;
-        // item.ParameterName= "Visual Leak Detector detected 1 memory leak (84 bytes)";
+        item.ParameterName= "Visual Leak Detector detected 1 memory leak (84 bytes)";
-        // item.sampleTime = "2024-9-10 11:22:33.444";
+        item.sampleTime = "2024-9-10 11:22:33.444";
-        // item.unit = "C";
+        item.unit = "C";
-        // item.value = "100";
+        item.value = QString("%1").arg(j++).toStdString();
-        // tbl_data.append(item);
+        tbl_data.append(item);
 
         std::string buf;
         for (unsigned int i = 0; i < mysql_num_fields(res); ++i)
         {
-            qDebug() << mysql_fetch_field_direct(res,i)->name ;
+            // qDebug() << mysql_fetch_field_direct(res,i)->name ;
-            QString field_name (mysql_fetch_field_direct(res,i)->name);
+            // QString field_name (mysql_fetch_field_direct(res,i)->name);
-            if (field_name == "data_timestamp")
+            // if (field_name == "data_timestamp")
-            {
+            // {
-                item.sampleTime = row[i];
+            //     item.sampleTime = row[i];
-                qDebug() << row[i];
+            //     qDebug() << row[i];
-            }
+            // }
-            else if (field_name == "data_content")
+            // else if (field_name == "data_content")
-            {
+            // {
-                std::string v(row[i]);
+            //     std::string v(row[i]);
-                qDebug() << Kutilities::printHex(v.c_str(),v.length()).c_str();
+            //     qDebug() << Kutilities::printHex(v.c_str(),v.length()).c_str();
-                ZipUtils::DecompressString(v.c_str(),v.length(),buf);
+            //     ZipUtils::DecompressString(v.c_str(),v.length(),buf);
-                qDebug() << buf.c_str();
+            //     qDebug() << buf.c_str();
-            }
+            // }
         }
         qDebug() << "\r\n";
     }

applications/emsConfigurer/mysqlutils.h

@@ -31,7 +31,7 @@ public:
     void CloseDatabase();
     bool OpenDatabase(const std::string& server = "127.0.0.1", int dbport = 3306, const std::string& dbuser = "root", const std::string& dbpasswd = "Hj57471000", const std::string& database="hjems");
 
-    int RetrieveTableData(TableData& tbl_data);
+    int RetrieveTableData(TableData& tbl_data,int retrieve_rows=100);
 
 private:
 #ifdef _USING_QT_MYSQL_CONNECTOR_