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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "bookwindow.h"
#include "bookdelegate.h"
#include "initdb.h"
#include <QApplication>
#include <QComboBox>
#include <QDataWidgetMapper>
#include <QGridLayout>
#include <QHeaderView>
#include <QLabel>
#include <QLineEdit>
#include <QMenu>
#include <QMenuBar>
#include <QMessageBox>
#include <QPainter>
#include <QScrollBar>
#include <QSpinBox>
#include <QSqlDatabase>
#include <QTableView>
BookWindow::BookWindow()
{
if (!QSqlDatabase::drivers().contains("QSQLITE"))
QMessageBox::critical(this, tr("Unable to load database"),
tr("This demo needs the SQLITE driver"));
// Initialize the database:
QSqlError err = initDb();
if (err.type() != QSqlError::NoError) {
showError(err);
return;
}
// create the central widget for the window
window = new QWidget(this);
setCentralWidget(window);
createLayout();
createModel();
// Populate the model
if (!model->select()) {
showError(model->lastError());
return;
}
configureWidgets();
// create the mappings between the UI elements and the SQL model
createMappings();
tableView->setCurrentIndex(model->index(0, 0));
tableView->selectRow(0);
createMenuBar();
}
void BookWindow::showError(const QSqlError &err)
{
QMessageBox::critical(this, tr("Unable to initialize Database"),
tr("Error initializing database: %1").arg(err.text()));
}
void BookWindow::createLayout()
{
tableView = new QTableView(window);
gridLayout = new QGridLayout(window);
titleLabel = new QLabel(tr("Title:"), window);
titleLineEdit = new QLineEdit(window);
authorLabel = new QLabel(tr("Author:"), window);
authorComboBox = new QComboBox(window);
genreLabel = new QLabel(tr("Genre:"), window);
genreComboBox = new QComboBox(window);
yearLabel = new QLabel(tr("Year:"), window);
yearSpinBox = new QSpinBox(window);
ratingLabel = new QLabel(tr("Rating:"), window);
ratingComboBox = new QComboBox(window);
gridLayout->addWidget(titleLabel, 0, 0, Qt::AlignRight);
gridLayout->addWidget(titleLineEdit, 0, 1, 1, 3);
gridLayout->addWidget(authorLabel, 1, 0, Qt::AlignRight);
gridLayout->addWidget(authorComboBox, 1, 1);
gridLayout->addWidget(yearLabel, 1, 2, Qt::AlignRight);
gridLayout->addWidget(yearSpinBox, 1, 3);
gridLayout->addWidget(genreLabel, 2, 0, Qt::AlignRight);
gridLayout->addWidget(genreComboBox, 2, 1);
gridLayout->addWidget(ratingLabel, 2, 2, Qt::AlignRight);
gridLayout->addWidget(ratingComboBox, 2, 3);
gridLayout->addWidget(tableView, 3, 0, 1, 4, Qt::AlignCenter);
gridLayout->setColumnStretch(1, 1000);
gridLayout->setColumnStretch(3, 1000);
gridLayout->setContentsMargins(18, 18, 18, 18);
gridLayout->setSpacing(18);
gridLayout->setAlignment(Qt::AlignHCenter);
}
void BookWindow::createModel()
{
model = new QSqlRelationalTableModel(tableView);
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->setTable("books");
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 localised 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"));
}
void BookWindow::configureWidgets()
{
tableView->setModel(model);
tableView->setItemDelegate(new BookDelegate(model->fieldIndex("rating"), tableView));
tableView->setColumnHidden(model->fieldIndex("id"), true);
tableView->verticalHeader()->setVisible(false);
tableView->setSelectionMode(QAbstractItemView::ExtendedSelection);
tableView->setSelectionBehavior(QAbstractItemView::SelectRows);
// Lock and prohibit resizing of the width of the columns
tableView->horizontalHeader()->setSectionResizeMode(QHeaderView::ResizeToContents);
tableView->verticalHeader()->setSectionResizeMode(QHeaderView::ResizeToContents);
tableView->horizontalHeader()->setFixedHeight(tableView->rowHeight(0));
// increment by two to consider the frame
tableView->setFixedWidth(tableView->horizontalHeader()->length() +
tableView->verticalScrollBar()->sizeHint().width() + 2);
tableView->setMaximumHeight(tableView->verticalHeader()->length() +
tableView->horizontalHeader()->height() + 2);
authorComboBox->setModel(model->relationModel(authorIdx));
authorComboBox->setModelColumn(model->relationModel(authorIdx)->fieldIndex("name"));
genreComboBox->setModel(model->relationModel(genreIdx));
genreComboBox->setModelColumn(model->relationModel(genreIdx)->fieldIndex("name"));
yearSpinBox->setMaximum(9999);
ratingComboBox->setItemDelegate(new BookDelegate(0, this));
ratingComboBox->setLabelDrawingMode(QComboBox::LabelDrawingMode::UseDelegate);
ratingComboBox->addItems({"0", "1", "2", "3", "4", "5"});
ratingComboBox->setIconSize(iconSize());
}
void BookWindow::createMappings()
{
QDataWidgetMapper *mapper = new QDataWidgetMapper(this);
mapper->setModel(model);
mapper->setItemDelegate(new BookDelegate(model->fieldIndex("rating"), this));
mapper->addMapping(titleLineEdit, model->fieldIndex("title"));
mapper->addMapping(yearSpinBox, model->fieldIndex("year"));
mapper->addMapping(authorComboBox, authorIdx);
mapper->addMapping(genreComboBox, genreIdx);
mapper->addMapping(ratingComboBox, model->fieldIndex("rating"), "currentIndex");
connect(tableView->selectionModel(),
&QItemSelectionModel::currentRowChanged,
mapper,
&QDataWidgetMapper::setCurrentModelIndex
);
}
void BookWindow::createMenuBar()
{
QAction *quitAction = new QAction(tr("&Quit"), this);
QAction *aboutAction = new QAction(tr("&About"), this);
QAction *aboutQtAction = new QAction(tr("&About Qt"), this);
QMenu *fileMenu = menuBar()->addMenu(tr("&File"));
fileMenu->addAction(quitAction);
QMenu *helpMenu = menuBar()->addMenu(tr("&Help"));
helpMenu->addAction(aboutAction);
helpMenu->addAction(aboutQtAction);
connect(quitAction, &QAction::triggered, qApp, &QCoreApplication::quit);
connect(aboutAction, &QAction::triggered, this, &BookWindow::about);
connect(aboutQtAction, &QAction::triggered, qApp, &QApplication::aboutQt);
}
void BookWindow::about()
{
QMessageBox::about(this, tr("About Books"),
tr("<p>The <b>Books</b> example shows how to use Qt SQL classes "
"with a model/view framework."));
}
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