using an isntance of QSqlDatabase for connection defiinition

[jfinn88]

Thank you for all the help anda_skoa,
Model seems to be working good now I will posted updated code
I'm now wanting to add some functionality to my tableView, Like to be able to search by date and userName... I want to pass text values back to my c++ function a would like to use the signal and slot mechanism to perform this action. However I get lost with what Object I need to pass the QObject::connect() method, for it to work.
I created two signals and two slots one for the date text field in qml and the other is for the userName text field in qml.
in C++ I created to slots to receive the qml signals and to out put the text data passed to the console using a debug() method.
I'm little confused on where to place the QObject::connect method in my project... main.cpp or sqliteModel.cpp in the constructor ?
I am unsure what objects to pass the connect() method for the signal to receive the slot ?
I would also Like to create a table in the database for each separate day for user event logging and delete old tables after 30 days
here is my code: (had to remove functions for model in cpp file to get it to fit)

=========== main.qml===============

import QtQuick 2.5
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.3
import QtQuick.Window 2.2
import QtQuick.Dialogs 1.2
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.4
 
Window {
    signal submitDateText(string text)
    signal submitUserNameText(string text)
    visible: true
    width: 760
    height: 450
    title: "User Event Log"
    TableView {
        width: 750;
        height: 350;
        anchors.centerIn: parent;
        horizontalScrollBarPolicy: 0
        frameVisible: true
        model: sqliteModel
        TableViewColumn {
                role: "id"
                title: "id"
                width: 100
            }
            TableViewColumn {
                role: "userName"
                title: "User Name"
                width: 200
            }
            TableViewColumn {
                role: "eventMessage"
                title: "Event Message"
                width: 200
            }
            TableViewColumn {
                role: "dateTime"
                title: "Date Time"
                width: 200
            }
    }
    RowLayout {
        id: row1
        x: 201
        y: 403
        anchors.horizontalCenter: parent.horizontalCenter;
        anchors.bottom: parent.bottom
        width: 750
        height: 47;
        clip: false
        opacity: 0.9
        Button {
            id: load_btn
            text: qsTr("Load")
            MouseArea{
                anchors.fill: parent
                onClicked: {
                    sqliteModel.dbConnect();
                    sqliteModel.sqlSelect();
                }
            }
        }
        Label {
            id: userNameLabel
            text: qsTr("User Name")
        }
        TextField {
            id: userNameTextField
            placeholderText: qsTr("User Name")
        }
        Label {
            id: dateLabel
            width: 39
            height: 17
            text: qsTr("Date")
        }
        TextField {
            id: dateTextField
            width: 125
            height: 25
            placeholderText: qsTr("mm//dd/yyyy")
        }
        Button {
            id: searchBtn
            text: qsTr("Search")
            MouseArea{
                anchors.fill: parent
                onClicked: {
                    // emit the submitTextField signal
                    submitDateText(dateTextField.text);
                    submitUserNameText(userNameTextField.text);
                }
            }
        }
        Button {
            id: exit_btn
            text: qsTr("Exit")
            MouseArea{
                anchors.fill: parent
                onClicked: close();
            }
        }
    }
}

import QtQuick 2.5
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.3
import QtQuick.Window 2.2
import QtQuick.Dialogs 1.2
import QtQuick.Layouts 1.1
import QtQuick.Controls 1.4

Window {
    signal submitDateText(string text)
    signal submitUserNameText(string text)
    visible: true
    width: 760
    height: 450
    title: "User Event Log"
    TableView {
        width: 750;
        height: 350;
        anchors.centerIn: parent;
        horizontalScrollBarPolicy: 0
        frameVisible: true
        model: sqliteModel
        TableViewColumn {
                role: "id"
                title: "id"
                width: 100
            }
            TableViewColumn {
                role: "userName"
                title: "User Name"
                width: 200
            }
            TableViewColumn {
                role: "eventMessage"
                title: "Event Message"
                width: 200
            }
            TableViewColumn {
                role: "dateTime"
                title: "Date Time"
                width: 200
            }
    }
    RowLayout {
        id: row1
        x: 201
        y: 403
        anchors.horizontalCenter: parent.horizontalCenter;
        anchors.bottom: parent.bottom
        width: 750
        height: 47;
        clip: false
        opacity: 0.9
        Button {
            id: load_btn
            text: qsTr("Load")
            MouseArea{
                anchors.fill: parent
                onClicked: {
                    sqliteModel.dbConnect();
                    sqliteModel.sqlSelect();
                }
            }
        }
        Label {
            id: userNameLabel
            text: qsTr("User Name")
        }
        TextField {
            id: userNameTextField
            placeholderText: qsTr("User Name")
        }
        Label {
            id: dateLabel
            width: 39
            height: 17
            text: qsTr("Date")
        }
        TextField {
            id: dateTextField
            width: 125
            height: 25
            placeholderText: qsTr("mm//dd/yyyy")
        }
        Button {
            id: searchBtn
            text: qsTr("Search")
            MouseArea{
                anchors.fill: parent
                onClicked: {
                    // emit the submitTextField signal
                    submitDateText(dateTextField.text);
                    submitUserNameText(userNameTextField.text);
                }
            }
        }
        Button {
            id: exit_btn
            text: qsTr("Exit")
            MouseArea{
                anchors.fill: parent
                onClicked: close();
            }
        }
    }
}

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=========== main.cpp===============

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QSqlDatabase>
#include "sqlitemodel.h"
#include <QUrl>
 
int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);
    sqliteModel *model = new sqliteModel;
    QQmlApplicationEngine engine;
    QQmlContext *contxt = engine.rootContext();
    contxt->setContextProperty("sqliteModel", model);
    engine.load(QUrl("qrc:/main.qml"));
    return app.exec();
}

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QSqlDatabase>
#include "sqlitemodel.h"
#include <QUrl>

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);
    sqliteModel *model = new sqliteModel;
    QQmlApplicationEngine engine;
    QQmlContext *contxt = engine.rootContext();
    contxt->setContextProperty("sqliteModel", model);
    engine.load(QUrl("qrc:/main.qml"));
    return app.exec();
}

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=========== sqliteModel.cpp==========

#include "sqlitemodel.h"
 
sqliteModel::sqliteModel(QObject *parent):QAbstractListModel(parent)
{
    // connect our QML signal to our C++ slot
    QObject::connect(/*QMLObject(?)*/, SIGNAL(submitDateText(QString)), this, SLOT(searchDateText(QString)));
}
 
sqliteModel::~sqliteModel()
{
}
 
void sqliteModel::createDailyTable()
{
    dbConnect();
    int addOne;
    QSqlQuery createTableQry(m_selectDataBase);
    createTableQry.prepare("CREATE TABLE userlogevents1 AS SELECT * FROM userlogevents WHERE 0");
    createTableQry.exec();
    m_selectDataBase.close();
}
 
void sqliteModel::deleteDailyTable()
{
    dbConnect();
    QSqlQuery selectTables(m_selectDataBase);
    //---Selects all tables older than 30 days in database | Gets date created---//
    selectTables.prepare("SELECT usereventlog, create_date FROM sys.tables WHERE DATEDIFF(day, create_date, getdate()) > 30");
    selectTables.exec();
    QString selectTableResult;
    selectTableResult = selectTables.value(0).toString();
    selectTableResult.append(selectTables.value(1).toString());
    selectTableResult.append(selectTables.value(2).toString());
    qDebug() << selectTableResult;
 
    //--- If the table is older than 30 days drop it---//
        QSqlQuery deleteTableQry(m_selectDataBase);
        deleteTableQry.prepare("DROP TABLE userlogevetns");
        deleteTableQry.exec();
        m_selectDataBase.close();
}
 
void sqliteModel::searchDateFcn(QString dateText)
{
    dbConnect();
    QSqlQuery searchDateQry(m_selectDataBase);
    searchDateQry.prepare("SELECT id, userName, eventMessage, dateTime FROM usereventlog WHERE userName = "+dateText);
    searchDateQry.exec();
    m_selectDataBase.close();
}
 
void sqliteModel::searchUserNameFcn(QString userNameText)
{
    dbConnect();
    QSqlQuery searchDateQry(m_selectDataBase);
    searchDateQry.prepare("SELECT id, userName, eventMessage, dateTime FROM usereventlog WHERE userName = "+ userNameText);
    searchDateQry.exec();
    m_selectDataBase.close();
}
 
void sqliteModel::searchDateText(const QString &dateText)
{
    qDebug() << "c++: sqliteModel::searchDateText:" << dateText;
}
 
void sqliteModel::searchUserNameText(const QString &userNameText)
{
    qDebug() << "c++: sqliteModel::searchUserNameText:" << userNameText;
}

#include "sqlitemodel.h"

sqliteModel::sqliteModel(QObject *parent):QAbstractListModel(parent)
{
    // connect our QML signal to our C++ slot
    QObject::connect(/*QMLObject(?)*/, SIGNAL(submitDateText(QString)), this, SLOT(searchDateText(QString)));
}

sqliteModel::~sqliteModel()
{
}

void sqliteModel::createDailyTable()
{
    dbConnect();
    int addOne;
    QSqlQuery createTableQry(m_selectDataBase);
    createTableQry.prepare("CREATE TABLE userlogevents1 AS SELECT * FROM userlogevents WHERE 0");
    createTableQry.exec();
    m_selectDataBase.close();
}

void sqliteModel::deleteDailyTable()
{
    dbConnect();
    QSqlQuery selectTables(m_selectDataBase);
    //---Selects all tables older than 30 days in database | Gets date created---//
    selectTables.prepare("SELECT usereventlog, create_date FROM sys.tables WHERE DATEDIFF(day, create_date, getdate()) > 30");
    selectTables.exec();
    QString selectTableResult;
    selectTableResult = selectTables.value(0).toString();
    selectTableResult.append(selectTables.value(1).toString());
    selectTableResult.append(selectTables.value(2).toString());
    qDebug() << selectTableResult;

    //--- If the table is older than 30 days drop it---//
        QSqlQuery deleteTableQry(m_selectDataBase);
        deleteTableQry.prepare("DROP TABLE userlogevetns");
        deleteTableQry.exec();
        m_selectDataBase.close();
}

void sqliteModel::searchDateFcn(QString dateText)
{
    dbConnect();
    QSqlQuery searchDateQry(m_selectDataBase);
    searchDateQry.prepare("SELECT id, userName, eventMessage, dateTime FROM usereventlog WHERE userName = "+dateText);
    searchDateQry.exec();
    m_selectDataBase.close();
}

void sqliteModel::searchUserNameFcn(QString userNameText)
{
    dbConnect();
    QSqlQuery searchDateQry(m_selectDataBase);
    searchDateQry.prepare("SELECT id, userName, eventMessage, dateTime FROM usereventlog WHERE userName = "+ userNameText);
    searchDateQry.exec();
    m_selectDataBase.close();
}

void sqliteModel::searchDateText(const QString &dateText)
{
    qDebug() << "c++: sqliteModel::searchDateText:" << dateText;
}

void sqliteModel::searchUserNameText(const QString &userNameText)
{
    qDebug() << "c++: sqliteModel::searchUserNameText:" << userNameText;
}

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=========== sqliteModel.h===============

#ifndef SQLITEMODEL_H
#define SQLITEMODEL_H
 
#include <assert.h>
#include <list>
#include <QList>
#include <QColor>
#include <QObject>
#include <QDebug>
#include <QString>
#include <QFileInfo>
#include <QDateTime>
#include <QQmlError>
#include <QQmlApplicationEngine>
#include <QQmlEngine>
#include <QQmlContext>
#include <QtSql/QSqlDatabase>
#include <QtSql/QSqlQuery>
#include <QtSql/QSqlError>
#include <QtSql/QSqlRecord>
#include <QModelIndex>
#include <QAbstractListModel>
 
struct userEventLogMsg{
  QString id;
  QString username;
  QString eventmessage;
  QString datetime;
};
 
class sqliteModel:public QAbstractListModel
{
    Q_OBJECT
public:
    explicit sqliteModel(QObject *parent = 0);
    ~sqliteModel();
    enum userEventRoles {idRole= Qt::UserRole + 220, nameRole, msgRole, dateRole};
    int rowCount(const QModelIndex & parent) const;
    QHash<int, QByteArray> roleNames() const;
    QVariant data(const QModelIndex &index, int role=Qt::DisplayRole) const;
    Q_INVOKABLE void addEvent(const userEventLogMsg &msg);
    Q_INVOKABLE void dbConnect();
    Q_INVOKABLE void sqlSelect();
    void createDailyTable();
    void deleteDailyTable();
    void searchDateFcn(QString userDateText);
    void searchUserNameFcn(QString userNameText);
public slots:
    void searchDateText(const QString &dateIn);
    void searchUserNameText(const QString &userNameIn);
private:
    QList<userEventLogMsg> m_msgList;
    QSqlDatabase m_selectDataBase;
    QSqlQuery m_selectQuery;
};

#ifndef SQLITEMODEL_H
#define SQLITEMODEL_H

#include <assert.h>
#include <list>
#include <QList>
#include <QColor>
#include <QObject>
#include <QDebug>
#include <QString>
#include <QFileInfo>
#include <QDateTime>
#include <QQmlError>
#include <QQmlApplicationEngine>
#include <QQmlEngine>
#include <QQmlContext>
#include <QtSql/QSqlDatabase>
#include <QtSql/QSqlQuery>
#include <QtSql/QSqlError>
#include <QtSql/QSqlRecord>
#include <QModelIndex>
#include <QAbstractListModel>

struct userEventLogMsg{
  QString id;
  QString username;
  QString eventmessage;
  QString datetime;
};

class sqliteModel:public QAbstractListModel
{
    Q_OBJECT
public:
    explicit sqliteModel(QObject *parent = 0);
    ~sqliteModel();
    enum userEventRoles {idRole= Qt::UserRole + 220, nameRole, msgRole, dateRole};
    int rowCount(const QModelIndex & parent) const;
    QHash<int, QByteArray> roleNames() const;
    QVariant data(const QModelIndex &index, int role=Qt::DisplayRole) const;
    Q_INVOKABLE void addEvent(const userEventLogMsg &msg);
    Q_INVOKABLE void dbConnect();
    Q_INVOKABLE void sqlSelect();
    void createDailyTable();
    void deleteDailyTable();
    void searchDateFcn(QString userDateText);
    void searchUserNameFcn(QString userNameText);
public slots:
    void searchDateText(const QString &dateIn);
    void searchUserNameText(const QString &userNameIn);
private:
    QList<userEventLogMsg> m_msgList;
    QSqlDatabase m_selectDataBase;
    QSqlQuery m_selectQuery;
};

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I was able to pass the text form qml to my cpp slot by expose Qt slot to QML element. By using the context property I set for my model to be exposed to QML.

now my searchDateText fcn and searchUserName fcn can be called in qml by:

Button {
            id: searchBtn
            text: qsTr("Search")
            MouseArea{
                anchors.fill: parent
                onClicked: {
                    sqliteModel.searchDateText(dateTextField.text);
                    sqliteModel.searchUserNameText(userNameTextField.text);
                }
            }
        }

Button {
            id: searchBtn
            text: qsTr("Search")
            MouseArea{
                anchors.fill: parent
                onClicked: {
                    sqliteModel.searchDateText(dateTextField.text);
                    sqliteModel.searchUserNameText(userNameTextField.text);
                }
            }
        }

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(?) I did the same for my dbConnect and sqlSelect fcns however I have to include Q_INVOKABLE when intializing them in the header file or for some reason or I cant call them in QML with out the Q_INVOKABLE keyword but my searchDateText & searchUserNameText fucntions do??? -> error: Property 'dbConnect' of object sqliteModel() is not a function

I would like to pass the QML text using a QML signal to a CPP slot using the QObject::connect() mainly for learning purposes... The objects that I need to pass the connect() method make more sense now, I need to pass a QML object for the qml signal() and pass a class object (sqliteModel) for the slot(), if I use the connect() method in my cpp class (in the constructor) I can use keyword "this" for the CPP object for the connect method?

[anda_skoa]

Like to be able to search by date and userName... I want to pass text values back to my c++ function a would like to use the signal and slot mechanism to perform this action. However I get lost with what Object I need to pass the QObject::connect() method, for it to work.
I created two signals and two slots one for the date text field in qml and the other is for the userName text field in qml.
in C++ I created to slots to receive the qml signals and to out put the text data passed to the console using a debug() method.
I'm little confused on where to place the QObject::connect method in my project... main.cpp or sqliteModel.cpp in the constructor ?
I am unsure what objects to pass the connect() method for the signal to receive the slot ?

You just call the slots directly.
Slots, like Q_INVOKABLE methods, can be called from QML.

Your QML code suggests that you want to pass both date and user name when clicking search, so a single slot with two arguments will do.

I would also Like to create a table in the database for each separate day for user event logging and delete old tables after 30 days
here is my code: (had to remove functions for model in cpp file to get it to fit)

I guess you have two options:
- use an additional table that maps from a date to a table name for that date
- encode the date in the table name

I was able to pass the text form qml to my cpp slot by expose Qt slot to QML element. By using the context property I set for my model to be exposed to QML.

Yes, exactly, though you probably want to use a single method if both inputs are to be used in the search.

(?) I did the same for my dbConnect and sqlSelect fcns however I have to include Q_INVOKABLE when intializing them in the header file or for some reason or I cant call them in QML with out the Q_INVOKABLE keyword but my searchDateText & searchUserNameText fucntions do??? -> error: Property 'dbConnect' of object sqliteModel() is not a function

They have to be slots or Q_INVOKABLE.

From the QML side's point of view there is actually no difference.
It is customary though to use Q_INVOKABLE when methods return something, as slots usually don't do that.

In your case all methods you have so far could be slots.

I would like to pass the QML text using a QML signal to a CPP slot using the QObject::connect() mainly for learning purposes...

I would advise against that, you would put effort into learning something that you then don't want to use.
I.e. you don't want your C++ code to be dependent on specific QML objects or their specific signals.

The objects that I need to pass the connect() method make more sense now, I need to pass a QML object for the qml signal() and pass a class object (sqliteModel) for the slot()

Yes, but you really don't want to do that.

if I use the connect() method in my cpp class (in the constructor) I can use keyword "this" for the CPP object for the connect method?

Theoretically yes, but the QML scene has not been loaded yet when the model's constructor runs, so the connect would have to happen from outside after both model and QML objects exist.

Cheers,
_