bookwindow.cpp Example File

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#include "bookwindow.h"
#include "bookdelegate.h"
#include "initdb.h"

#include <QtSql>


    if (!QSqlDatabase::drivers().contains("QSQLITE"))
        QMessageBox::critical(this, "Unable to load database", "This demo needs the SQLITE driver");

    // initialize the database
    QSqlError err = initDb();
    if (err.type() != QSqlError::NoError) {

    // Create the data model
    model = new QSqlRelationalTableModel(ui.bookTable);

    // Remember the indexes of the columns
    authorIdx = model->fieldIndex("author");
    genreIdx = model->fieldIndex("genre");

    // Set the relations to the other database tables
    model->setRelation(authorIdx, QSqlRelation("authors", "id", "name"));
    model->setRelation(genreIdx, QSqlRelation("genres", "id", "name"));

    // Set the localized header captions
    model->setHeaderData(authorIdx, Qt::Horizontal, tr("Author Name"));
    model->setHeaderData(genreIdx, Qt::Horizontal, tr("Genre"));
    model->setHeaderData(model->fieldIndex("title"), Qt::Horizontal, tr("Title"));
    model->setHeaderData(model->fieldIndex("year"), Qt::Horizontal, tr("Year"));
    model->setHeaderData(model->fieldIndex("rating"), Qt::Horizontal, tr("Rating"));

    // Populate the model
    if (!model->select()) {

    // Set the model and hide the ID column
    ui.bookTable->setItemDelegate(new BookDelegate(ui.bookTable));
    ui.bookTable->setColumnHidden(model->fieldIndex("id"), true);

    // Initialize the Author combo box


    QDataWidgetMapper *mapper = new QDataWidgetMapper(this);
    mapper->setItemDelegate(new BookDelegate(this));
    mapper->addMapping(ui.titleEdit, model->fieldIndex("title"));
    mapper->addMapping(ui.yearEdit, model->fieldIndex("year"));
    mapper->addMapping(ui.authorEdit, authorIdx);
    mapper->addMapping(ui.genreEdit, genreIdx);
    mapper->addMapping(ui.ratingEdit, model->fieldIndex("rating"));

    connect(ui.bookTable->selectionModel(), SIGNAL(currentRowChanged(QModelIndex,QModelIndex)),
            mapper, SLOT(setCurrentModelIndex(QModelIndex)));

    ui.bookTable->setCurrentIndex(model->index(0, 0));

void BookWindow::showError(const QSqlError &err)
    QMessageBox::critical(this, "Unable to initialize Database",
                "Error initializing database: " + err.text());

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