Qt 5.11 | Qt Widgets | Editable Tree Model Example | mainwindow.cpp Example File

Qt 5.11.3 Reference Documentation

# mainwindow.cpp Example File

itemviews/editabletreemodel/mainwindow.cpp

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      #include "mainwindow.h"
      #include "treemodel.h"

      #include <QFile>

      MainWindow::MainWindow(QWidget *parent)
          : QMainWindow(parent)
      {
          setupUi(this);

          QStringList headers;
          headers << tr("Title") << tr("Description");

          QFile file(":/default.txt");
          file.open(QIODevice::ReadOnly);
          TreeModel *model = new TreeModel(headers, file.readAll());
          file.close();

          view->setModel(model);
          for (int column = 0; column < model->columnCount(); ++column)
              view->resizeColumnToContents(column);

          connect(exitAction, &QAction::triggered, qApp, &QCoreApplication::quit);

          connect(view->selectionModel(), &QItemSelectionModel::selectionChanged,
                  this, &MainWindow::updateActions);

          connect(actionsMenu, &QMenu::aboutToShow, this, &MainWindow::updateActions);
          connect(insertRowAction, &QAction::triggered, this, &MainWindow::insertRow);
          connect(insertColumnAction, &QAction::triggered, this, &MainWindow::insertColumn);
          connect(removeRowAction, &QAction::triggered, this, &MainWindow::removeRow);
          connect(removeColumnAction, &QAction::triggered, this, &MainWindow::removeColumn);
          connect(insertChildAction, &QAction::triggered, this, &MainWindow::insertChild);

          updateActions();
      }

      void MainWindow::insertChild()
      {
          QModelIndex index = view->selectionModel()->currentIndex();
          QAbstractItemModel *model = view->model();

          if (model->columnCount(index) == 0) {
              if (!model->insertColumn(0, index))
                  return;
          }

          if (!model->insertRow(0, index))
              return;

          for (int column = 0; column < model->columnCount(index); ++column) {
              QModelIndex child = model->index(0, column, index);
              model->setData(child, QVariant("[No data]"), Qt::EditRole);
              if (!model->headerData(column, Qt::Horizontal).isValid())
                  model->setHeaderData(column, Qt::Horizontal, QVariant("[No header]"), Qt::EditRole);
          }

          view->selectionModel()->setCurrentIndex(model->index(0, 0, index),
                                                  QItemSelectionModel::ClearAndSelect);
          updateActions();
      }

      bool MainWindow::insertColumn()
      {
          QAbstractItemModel *model = view->model();
          int column = view->selectionModel()->currentIndex().column();

          // Insert a column in the parent item.
          bool changed = model->insertColumn(column + 1);
          if (changed)
              model->setHeaderData(column + 1, Qt::Horizontal, QVariant("[No header]"), Qt::EditRole);

          updateActions();

          return changed;
      }

      void MainWindow::insertRow()
      {
          QModelIndex index = view->selectionModel()->currentIndex();
          QAbstractItemModel *model = view->model();

          if (!model->insertRow(index.row()+1, index.parent()))
              return;

          updateActions();

          for (int column = 0; column < model->columnCount(index.parent()); ++column) {
              QModelIndex child = model->index(index.row()+1, column, index.parent());
              model->setData(child, QVariant("[No data]"), Qt::EditRole);
          }
      }

      bool MainWindow::removeColumn()
      {
          QAbstractItemModel *model = view->model();
          int column = view->selectionModel()->currentIndex().column();

          // Insert columns in each child of the parent item.
          bool changed = model->removeColumn(column);

          if (changed)
              updateActions();

          return changed;
      }

      void MainWindow::removeRow()
      {
          QModelIndex index = view->selectionModel()->currentIndex();
          QAbstractItemModel *model = view->model();
          if (model->removeRow(index.row(), index.parent()))
              updateActions();
      }

      void MainWindow::updateActions()
      {
          bool hasSelection = !view->selectionModel()->selection().isEmpty();
          removeRowAction->setEnabled(hasSelection);
          removeColumnAction->setEnabled(hasSelection);

          bool hasCurrent = view->selectionModel()->currentIndex().isValid();
          insertRowAction->setEnabled(hasCurrent);
          insertColumnAction->setEnabled(hasCurrent);

          if (hasCurrent) {
              view->closePersistentEditor(view->selectionModel()->currentIndex());

              int row = view->selectionModel()->currentIndex().row();
              int column = view->selectionModel()->currentIndex().column();
              if (view->selectionModel()->currentIndex().parent().isValid())
                  statusBar()->showMessage(tr("Position: (%1,%2)").arg(row).arg(column));
              else
                  statusBar()->showMessage(tr("Position: (%1,%2) in top level").arg(row).arg(column));
          }
      }