Qt 5.6 | Qt SQL | SQL Browser | connectionwidget.cpp Example File

Qt 5.6.2 Reference Documentation

# connectionwidget.cpp Example File

sqlbrowser/connectionwidget.cpp

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      #include "connectionwidget.h"

      #include <QtWidgets>
      #include <QtSql>

      ConnectionWidget::ConnectionWidget(QWidget *parent)
          : QWidget(parent)
      {
          QVBoxLayout *layout = new QVBoxLayout(this);
          tree = new QTreeWidget(this);
          tree->setObjectName(QLatin1String("tree"));
          tree->setHeaderLabels(QStringList(tr("database")));
          tree->header()->setSectionResizeMode(QHeaderView::Stretch);
          QAction *refreshAction = new QAction(tr("Refresh"), tree);
          metaDataAction = new QAction(tr("Show Schema"), tree);
          connect(refreshAction, SIGNAL(triggered()), SLOT(refresh()));
          connect(metaDataAction, SIGNAL(triggered()), SLOT(showMetaData()));
          tree->addAction(refreshAction);
          tree->addAction(metaDataAction);
          tree->setContextMenuPolicy(Qt::ActionsContextMenu);

          layout->addWidget(tree);

          QMetaObject::connectSlotsByName(this);
      }

      ConnectionWidget::~ConnectionWidget()
      {
      }

      static QString qDBCaption(const QSqlDatabase &db)
      {
          QString nm = db.driverName();
          nm.append(QLatin1Char(':'));
          if (!db.userName().isEmpty())
              nm.append(db.userName()).append(QLatin1Char('@'));
          nm.append(db.databaseName());
          return nm;
      }

      void ConnectionWidget::refresh()
      {
          tree->clear();
          QStringList connectionNames = QSqlDatabase::connectionNames();

          bool gotActiveDb = false;
          for (int i = 0; i < connectionNames.count(); ++i) {
              QTreeWidgetItem *root = new QTreeWidgetItem(tree);
              QSqlDatabase db = QSqlDatabase::database(connectionNames.at(i), false);
              root->setText(0, qDBCaption(db));
              if (connectionNames.at(i) == activeDb) {
                  gotActiveDb = true;
                  setActive(root);
              }
              if (db.isOpen()) {
                  QStringList tables = db.tables();
                  for (int t = 0; t < tables.count(); ++t) {
                      QTreeWidgetItem *table = new QTreeWidgetItem(root);
                      table->setText(0, tables.at(t));
                  }
              }
          }
          if (!gotActiveDb) {
              activeDb = connectionNames.value(0);
              setActive(tree->topLevelItem(0));
          }

          tree->doItemsLayout(); // HACK
      }

      QSqlDatabase ConnectionWidget::currentDatabase() const
      {
          return QSqlDatabase::database(activeDb);
      }

      static void qSetBold(QTreeWidgetItem *item, bool bold)
      {
          QFont font = item->font(0);
          font.setBold(bold);
          item->setFont(0, font);
      }

      void ConnectionWidget::setActive(QTreeWidgetItem *item)
      {
          for (int i = 0; i < tree->topLevelItemCount(); ++i) {
              if (tree->topLevelItem(i)->font(0).bold())
                  qSetBold(tree->topLevelItem(i), false);
          }

          if (!item)
              return;

          qSetBold(item, true);
          activeDb = QSqlDatabase::connectionNames().value(tree->indexOfTopLevelItem(item));
      }

      void ConnectionWidget::on_tree_itemActivated(QTreeWidgetItem *item, int /* column */)
      {

          if (!item)
              return;

          if (!item->parent()) {
              setActive(item);
          } else {
              setActive(item->parent());
              emit tableActivated(item->text(0));
          }
      }

      void ConnectionWidget::showMetaData()
      {
          QTreeWidgetItem *cItem = tree->currentItem();
          if (!cItem || !cItem->parent())
              return;
          setActive(cItem->parent());
          emit metaDataRequested(cItem->text(0));
      }

      void ConnectionWidget::on_tree_currentItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *)
      {
          metaDataAction->setEnabled(current && current->parent());
      }