Qt数据库代码实例（各数据库通用）

#include "mainwindow.h" #include <QGridLayout> #include <QAbstractItemView> #include <QHeaderView> #include <QAction> #include <QMenu> #include <QMenuBar> #include <QMessageBox> #include <QSqlRecord> #include "editdialog.h" extern int uniqueCarId; extern int uniqueFactoryId; MainWindow::MainWindow(const QString &factoryTable,const QString &carTable,QFile *carDetails,QWidget *parent) : QMainWindow(parent) { file = carDetails; readCarData(); carModel = new QSqlRelationalTableModel(this); carModel->setTable(carTable); carModel->setRelation(2, QSqlRelation(factoryTable, "id", "manufactory")); carModel->select(); factoryModel = new QSqlTableModel(this); factoryModel->setTable(factoryTable); factoryModel->select(); QGroupBox *factory = createFactoryGroupBox(); QGroupBox *cars = createCarGroupBox(); QGroupBox *details = createDetailsGroupBox(); uniqueCarId = carModel->rowCount(); uniqueFactoryId = factoryModel->rowCount(); //布局 QGridLayout *layout = new QGridLayout; layout->addWidget(factory, 0, 0); layout->addWidget(cars, 1, 0); layout->addWidget(details, 0, 1, 2, 1); layout->setColumnStretch(1, 1); layout->setColumnMinimumWidth(0, 500); QWidget *widget = new QWidget; widget->setLayout(layout); setCentralWidget(widget); createMenuBar(); resize(850, 400); setWindowTitle(tr("主从视图")); } MainWindow::~MainWindow() { } QGroupBox* MainWindow::createFactoryGroupBox() { factoryView = new QTableView; factoryView->setEditTriggers(QAbstractItemView::NoEditTriggers); factoryView->setSortingEnabled(true); factoryView->setSelectionBehavior(QAbstractItemView::SelectRows); factoryView->setSelectionMode(QAbstractItemView::SingleSelection); factoryView->setShowGrid(false); factoryView->setAlternatingRowColors(true); factoryView->setModel(factoryModel); connect(factoryView,SIGNAL(clicked (QModelIndex )),this,SLOT(changeFactory(QModelIndex))); QGroupBox *box = new QGroupBox(tr("汽车制造商")); QGridLayout *layout = new QGridLayout; layout->addWidget(factoryView, 0, 0); box->setLayout(layout); return box; } QGroupBox* MainWindow::createCarGroupBox() { QGroupBox *box = new QGroupBox(tr("汽车")); carView = new QTableView; carView->setEditTriggers(QAbstractItemView::NoEditTriggers); carView->setSortingEnabled(true); carView->setSelectionBehavior(QAbstractItemView::SelectRows); carView->setSelectionMode(QAbstractItemView::SingleSelection); carView->setShowGrid(false); carView->verticalHeader()->hide(); carView->setAlternatingRowColors(true); carView->setModel(carModel); connect(carView, SIGNAL(clicked(QModelIndex)),this,SLOT(showCarDetails(QModelIndex))); connect(carView, SIGNAL(activated(QModelIndex)),this,SLOT(showCarDetails(QModelIndex))); QVBoxLayout *layout = new QVBoxLayout; layout->addWidget(carView, 0, 0); box->setLayout(layout); return box; } QGroupBox* MainWindow::createDetailsGroupBox() { QGroupBox *box = new QGroupBox(tr("详细信息")); profileLabel = new QLabel; profileLabel->setWordWrap(true); profileLabel->setAlignment(Qt::AlignBottom); titleLabel = new QLabel; titleLabel->setWordWrap(true); titleLabel->setAlignment(Qt::AlignBottom); attribList = new QListWidget; QGridLayout *layout = new QGridLayout; layout->addWidget(profileLabel, 0, 0, 1, 2); layout->addWidget(titleLabel, 1, 0, 1, 2); layout->addWidget(attribList, 2, 0, 1, 2); layout->setRowStretch(2, 1); box->setLayout(layout); return box; } void MainWindow::createMenuBar() { QAction *addAction = new QAction(tr("添加"), this); QAction *deleteAction = new QAction(tr("删除"), this); QAction *quitAction = new QAction(tr("退出"), this); addAction->setShortcut(tr("Ctrl+A")); deleteAction->setShortcut(tr("Ctrl+D")); quitAction->setShortcut(tr("Ctrl+Q")); QMenu *fileMenu = menuBar()->addMenu(tr("操作菜单")); fileMenu->addAction(addAction); fileMenu->addAction(deleteAction); fileMenu->addSeparator(); fileMenu->addAction(quitAction); connect(addAction, SIGNAL(triggered(bool)), this, SLOT(addCar())); connect(deleteAction, SIGNAL(triggered(bool)), this, SLOT(delCar())); connect(quitAction, SIGNAL(triggered(bool)), this, SLOT(close())); } void MainWindow::changeFactory(QModelIndex index) { QSqlRecord record = factoryModel->record(index.row()); QString factoryId = record.value("id").toString(); carModel->setFilter("id = '"+ factoryId +"'") ; showFactorytProfile(index); } void MainWindow::showFactorytProfile(QModelIndex index) { QSqlRecord record = factoryModel->record(index.row()); QString name = record.value("manufactory").toString(); int count = carModel->rowCount(); profileLabel->setText(tr("汽车制造商 : %1 \n产品数量: %2").arg(name).arg(count)); profileLabel->show(); titleLabel->hide(); attribList->hide(); } void MainWindow::showCarDetails(QModelIndex index) { QSqlRecord record = carModel->record(index.row()); QString factory = record.value("manufactory").toString(); QString name = record.value("name").toString(); QString year = record.value("year").toString(); QString carId = record.value("carid").toString(); showFactorytProfile(indexOfFactory(factory)); titleLabel->setText(tr("品牌: %1 (%2)").arg(name).arg(year)); titleLabel->show(); QDomNodeList cars = carData.elementsByTagName("car"); for (int i = 0; i < cars.count(); i++) { QDomNode car = cars.item(i); if (car.toElement().attribute("id") == carId) { getAttribList(car.toElement()); break; } } if (!attribList->count() == 0) attribList->show(); } void MainWindow::getAttribList(QDomNode car) { attribList->clear(); QDomNodeList attribs = car.childNodes(); QDomNode node; QString attribNumber; for (int j = 0; j < attribs.count(); j++) { node = attribs.item(j); attribNumber = node.toElement().attribute("number"); QListWidgetItem *item = new QListWidgetItem(attribList); QString showText(attribNumber + ": " + node.toElement().text()); item->setText(tr("%1").arg(showText)); } } void MainWindow::delCar() { QModelIndexList selection = carView->selectionModel()->selectedRows(0); if (!selection.empty()) { QModelIndex idIndex = selection.at(0); int id = idIndex.data().toInt(); QString name = idIndex.sibling(idIndex.row(), 1).data().toString(); QString factory = idIndex.sibling(idIndex.row(), 2).data().toString(); QMessageBox::StandardButton button; button = QMessageBox::question(this,tr("删除汽车记录"),QString(tr("确认删除由'%1'生产的'%2'吗？").arg(factory).arg(name)),QMessageBox::Yes|QMessageBox::No); if(button == QMessageBox::Yes) { removeCarFromFile(id); removeCarFromDatabase(idIndex); decreaseCarCount(indexOfFactory(factory)); }else{ QMessageBox::information(this, tr("删除汽车记录"),tr("请选择要删除的记录。")); } } } void MainWindow::removeCarFromFile(int id) { QDomNodeList cars = carData.elementsByTagName("car"); for (int i = 0; i< cars.count(); i++) { QDomNode node = cars.item(i); if (node.toElement().attribute("id").toInt() == id) { carData.elementsByTagName("archive").item(0).removeChild(node); break; } } } void MainWindow::removeCarFromDatab