Passing Data with Qt's QSqlQueryModel

Question

Can someone help me figure out what I am doing wrong?

I am trying to pass QSqlQueryModel reference to my List widget so it can add list items. This code below should clear db contents of my table for now as a test because I plan on building QWidgetMapper into List later.

Code & Edit! 8-15 @ 1:50 PST

This is my error: ( Line error numbers do not match below code.)

1. ..\DBWidgetMap\trackersql.cpp: In member function 'QSqlQueryModel* TrackerSql::getListModel()':
2. ..\DBWidgetMap\trackersql.cpp:38: error: cannot convert 'QSqlQueryModel' to 'QSqlQueryModel*' in return

Here are what the classes do:

MainWindow : Main control class.

TrackerSQL : Sql queries.

List: Widget manages visual representation of ListUI.

ListUI: Visual representation for List. ( Not shown below, no need)

• MainWindow - > (TrackerSql, List = ( ListUI ))

Code: MainWindow

#include <QtGui/QMainWindow>
#include <QLayout>
#include "list.h"
#include "trackersql.h"

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();

    void windowFields(void);        // Set the `MainWindow` widget's to be displayed.
    void createWindowFields(void);  // Create widget fields to be displayed.
    void arrangeWindowFields(void); // Arrange the `MainWindow` layout.

    List *cardList;                 // Visual widget for display. Holds a list of cards in database.
    TrackerSql *sqlModel;           // Access to database queries.

    QHBoxLayout *hCard;             // Layout container for `MainWindow`.
};

MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent){
    QWidget *mainW = new QWidget;
    setCentralWidget(mainW);

    windowFields();

    mainW->setLayout(hCard);
} 

MainWindow::~MainWindow(){} 

void MainWindow::windowFields(void){
    // it works
} 

void MainWindow::createWindowFields(void){
    sqlModel = new TrackerSql;
    cardList = new List(sqlModel->getListModel(), this);
} 

void MainWindow::arrangeWindowFields(void){
    // it works...
} 

Code: TrackerSQL

#include <QWidget>
#include <QtSql>

class TrackerSql : public QWidget
{
    Q_OBJECT
public:
    explicit TrackerSql(QWidget *parent = 0);

    void connectSQL(void);        // Start sql connections and initialize `dbQuery`(s).
    void setConnection(void);     // Set the connection parameters.
    void createConnection(void);  // Start the `db` connection.

    void createTableQuerys(void); // Create `dbQuery`(s).

    QSqlQueryModel *getListModel(void);// Pass the refference location to query results

    QSqlDatabase    db;
    QSqlQueryModel  dbQueryCard;
    QString         // connection variables... 
};

TrackerSql::TrackerSql(QWidget *parent) :
    QWidget(parent)
{
    db = QSqlDatabase::addDatabase("QMYSQL");
    connectSQL();
}

void TrackerSql::connectSQL(void){
    setConnection();
    createConnection();
    createTableQuerys();
}

void TrackerSql::setConnection(void){
    // it works...
}

void TrackerSql::createConnection(void){
    // it works...
    db.open();
}

void TrackerSql::createTableQuerys(void){
    dbQueryCard.setQuery("SELECT * FROM Card");
}

QSqlQueryModel *TrackerSql::getListModel(void){
    return dbQueryCard;
}

Code: List

#include "listui.h"
#include <QSqlQueryModel>
#include <QWidgetMapper>

class List : public ListUI {
    Q_OBJECT
public:
    explicit List(QSqlQueryModel *model, QWidget *parent); // Initialize with model reference location of model.
    void setListItems(QSqlQueryModel *model);   // Set card list. (currently in debug output mode for test)  
};

List::List(QSqlQueryModel *model, QWidget *parent) :  ListUI(parent){
    setListItems(model);
}

void List::setListItems(QSqlQueryModel *model){
    model->clear();
}

Also can I propose a moderator add the tag Qt?

Answer 1

Advice from StackOverflow along with the below change to above. Other changes from advice are already reflected in code.

QSqlQueryModel *TrackerSql::getListModel(void){
    return &dbQueryCard;
}