browser.cpp Example File

sqlbrowser/browser.cpp
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#include "browser.h" #include "qsqlconnectiondialog.h" #include <QtWidgets> #include <QtSql> Browser::Browser(QWidget *parent) : QWidget(parent) { setupUi(this); table->addAction(insertRowAction); table->addAction(deleteRowAction); table->addAction(fieldStrategyAction); table->addAction(rowStrategyAction); table->addAction(manualStrategyAction); table->addAction(submitAction); table->addAction(revertAction); table->addAction(selectAction); if (QSqlDatabase::drivers().isEmpty()) QMessageBox::information(this, tr("No database drivers found"), tr("This demo requires at least one Qt database driver. " "Please check the documentation how to build the " "Qt SQL plugins.")); emit statusMessage(tr("Ready.")); } Browser::~Browser() { } void Browser::exec() { QSqlQueryModel *model = new QSqlQueryModel(table); model->setQuery(QSqlQuery(sqlEdit->toPlainText(), connectionWidget->currentDatabase())); table->setModel(model); if (model->lastError().type() != QSqlError::NoError) emit statusMessage(model->lastError().text()); else if (model->query().isSelect()) emit statusMessage(tr("Query OK.")); else emit statusMessage(tr("Query OK, number of affected rows: %1").arg( model->query().numRowsAffected())); updateActions(); } QSqlError Browser::addConnection(const QString &driver, const QString &dbName, const QString &host, const QString &user, const QString &passwd, int port) { static int cCount = 0; QSqlError err; QSqlDatabase db = QSqlDatabase::addDatabase(driver, QString("Browser%1").arg(++cCount)); db.setDatabaseName(dbName); db.setHostName(host); db.setPort(port); if (!db.open(user, passwd)) { err = db.lastError(); db = QSqlDatabase(); QSqlDatabase::removeDatabase(QString("Browser%1").arg(cCount)); } connectionWidget->refresh(); return err; } void Browser::addConnection() { QSqlConnectionDialog dialog(this); if (dialog.exec() != QDialog::Accepted) return; if (dialog.useInMemoryDatabase()) { QSqlDatabase::database("in_mem_db", false).close(); QSqlDatabase::removeDatabase("in_mem_db"); QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", "in_mem_db"); db.setDatabaseName(":memory:"); if (!db.open()) QMessageBox::warning(this, tr("Unable to open database"), tr("An error occurred while " "opening the connection: ") + db.lastError().text()); QSqlQuery q("", db); q.exec("drop table Movies"); q.exec("drop table Names"); q.exec("create table Movies (id integer primary key, Title varchar, Director varchar, Rating number)"); q.exec("insert into Movies values (0, 'Metropolis', 'Fritz Lang', '8.4')"); q.exec("insert into Movies values (1, 'Nosferatu, eine Symphonie des Grauens', 'F.W. Murnau', '8.1')"); q.exec("insert into Movies values (2, 'Bis ans Ende der Welt', 'Wim Wenders', '6.5')"); q.exec("insert into Movies values (3, 'Hardware', 'Richard Stanley', '5.2')"); q.exec("insert into Movies values (4, 'Mitchell', 'Andrew V. McLaglen', '2.1')"); q.exec("create table Names (id integer primary key, Firstname varchar, Lastname varchar, City varchar)"); q.exec("insert into Names values (0, 'Sala', 'Palmer', 'Morristown')"); q.exec("insert into Names values (1, 'Christopher', 'Walker', 'Morristown')"); q.exec("insert into Names values (2, 'Donald', 'Duck', 'Andeby')"); q.exec("insert into Names values (3, 'Buck', 'Rogers', 'Paris')"); q.exec("insert into Names values (4, 'Sherlock', 'Holmes', 'London')"); connectionWidget->refresh(); } else { QSqlError err = addConnection(dialog.driverName(), dialog.databaseName(), dialog.hostName(), dialog.userName(), dialog.password(), dialog.port()); if (err.type() != QSqlError::NoError) QMessageBox::warning(this, tr("Unable to open database"), tr("An error occurred while " "opening the connection: ") + err.text()); } } void Browser::showTable(const QString &t) { QSqlTableModel *model = new CustomModel(table, connectionWidget->currentDatabase()); model->setEditStrategy(QSqlTableModel::OnRowChange); model->setTable(connectionWidget->currentDatabase().driver()->escapeIdentifier(t, QSqlDriver::TableName)); model->select(); if (model->lastError().type() != QSqlError::NoError) emit statusMessage(model->lastError().text()); table->setModel(model); table->setEditTriggers(QAbstractItemView::DoubleClicked|QAbstractItemView::EditKeyPressed); connect(table->selectionModel(), &QItemSelectionModel::currentRowChanged, this, &Browser::currentChanged); updateActions(); } void Browser::showMetaData(const QString &t) { QSqlRecord rec = connectionWidget->currentDatabase().record(t); QStandardItemModel *model = new QStandardItemModel(table); model->insertRows(0, rec.count()); model->insertColumns(0, 7); model->setHeaderData(0, Qt::Horizontal, "Fieldname"); model->setHeaderData(1, Qt::Horizontal, "Type"); model->setHeaderData(2, Qt::Horizontal, "Length"); model->setHeaderData(3, Qt::Horizontal, "Precision"); model->setHeaderData(4, Qt::Horizontal, "Required"); model->setHeaderData(5, Qt::Horizontal, "AutoValue"); model->setHeaderData(6, Qt::Horizontal, "DefaultValue"); for (int i = 0; i < rec.count(); ++i) { QSqlField fld = rec.field(i); model->setData(model->index(i, 0), fld.name()); model->setData(model->index(i, 1), fld.typeID() == -1 ? QString(QMetaType::typeName(fld.type())) : QString("%1 (%2)").arg(QMetaType::typeName(fld.type())).arg(fld.typeID())); model->setData(model->index(i, 2), fld.length()); model->setData(model->index(i, 3), fld.precision()); model->setData(model->index(i, 4), fld.requiredStatus() == -1 ? QVariant("?") : QVariant(bool(fld.requiredStatus()))); model->setData(model->index(i, 5), fld.isAutoValue()); model->setData(model->index(i, 6), fld.defaultValue()); } table->setModel(model); table->setEditTriggers(QAbstractItemView::NoEditTriggers); updateActions(); } void Browser::insertRow() { QSqlTableModel *model = qobject_cast<QSqlTableModel *>(table->model()); if (!model) return; QModelIndex insertIndex = table->currentIndex(); int row = insertIndex.row() == -1 ? 0 : insertIndex.row(); model->insertRow(row); insertIndex = model->index(row, 0); table->setCurrentIndex(insertIndex); table->edit(insertIndex); } void Browser::deleteRow() { QSqlTableModel *model = qobject_cast<QSqlTableModel *>(table->model()); if (!model) return; QModelIndexList currentSelection = table->selectionModel()->selectedIndexes(); for (int i = 0; i < currentSelection.count(); ++i) { if (currentSelection.at(i).column() != 0) continue; model->removeRow(currentSelection.at(i).row()); } updateActions(); } void Browser::updateActions() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); bool enableIns = tm; bool enableDel = enableIns && table->currentIndex().isValid(); insertRowAction->setEnabled(enableIns); deleteRowAction->setEnabled(enableDel); fieldStrategyAction->setEnabled(tm); rowStrategyAction->setEnabled(tm); manualStrategyAction->setEnabled(tm); submitAction->setEnabled(tm); revertAction->setEnabled(tm); selectAction->setEnabled(tm); if (tm) { QSqlTableModel::EditStrategy es = tm->editStrategy(); fieldStrategyAction->setChecked(es == QSqlTableModel::OnFieldChange); rowStrategyAction->setChecked(es == QSqlTableModel::OnRowChange); manualStrategyAction->setChecked(es == QSqlTableModel::OnManualSubmit); } } void Browser::about() { QMessageBox::about(this, tr("About"), tr("The SQL Browser demonstration " "shows how a data browser can be used to visualize the results of SQL" "statements on a live database")); } void Browser::on_fieldStrategyAction_triggered() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); if (tm) tm->setEditStrategy(QSqlTableModel::OnFieldChange); } void Browser::on_rowStrategyAction_triggered() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); if (tm) tm->setEditStrategy(QSqlTableModel::OnRowChange); } void Browser::on_manualStrategyAction_triggered() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); if (tm) tm->setEditStrategy(QSqlTableModel::OnManualSubmit); } void Browser::on_submitAction_triggered() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); if (tm) tm->submitAll(); } void Browser::on_revertAction_triggered() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); if (tm) tm->revertAll(); } void Browser::on_selectAction_triggered() { QSqlTableModel * tm = qobject_cast<QSqlTableModel *>(table->model()); if (tm) tm->select(); }

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