freezetablewidget.cpp Example File

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  #include "freezetablewidget.h"

  #include <QScrollBar>
  #include <QHeaderView>

  FreezeTableWidget::FreezeTableWidget(QAbstractItemModel * model)
  {
        setModel(model);
        frozenTableView = new QTableView(this);

        init();

        //connect the headers and scrollbars of both tableviews together
        connect(horizontalHeader(),&QHeaderView::sectionResized, this,
                &FreezeTableWidget::updateSectionWidth);
        connect(verticalHeader(),&QHeaderView::sectionResized, this,
                &FreezeTableWidget::updateSectionHeight);

        connect(frozenTableView->verticalScrollBar(), &QAbstractSlider::valueChanged,
                verticalScrollBar(), &QAbstractSlider::setValue);
        connect(verticalScrollBar(), &QAbstractSlider::valueChanged,
                frozenTableView->verticalScrollBar(), &QAbstractSlider::setValue);

  }

  FreezeTableWidget::~FreezeTableWidget()
  {
        delete frozenTableView;
  }

  void FreezeTableWidget::init()
  {
        frozenTableView->setModel(model());
        frozenTableView->setFocusPolicy(Qt::NoFocus);
        frozenTableView->verticalHeader()->hide();
        frozenTableView->horizontalHeader()->setSectionResizeMode(QHeaderView::Fixed);

        viewport()->stackUnder(frozenTableView);

        frozenTableView->setStyleSheet("QTableView { border: none;"
                                       "background-color: #8EDE21;"
                                       "selection-background-color: #999}"); //for demo purposes
        frozenTableView->setSelectionModel(selectionModel());
        for (int col = 1; col < model()->columnCount(); ++col)
              frozenTableView->setColumnHidden(col, true);

        frozenTableView->setColumnWidth(0, columnWidth(0) );

        frozenTableView->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
        frozenTableView->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
        frozenTableView->show();

        updateFrozenTableGeometry();

        setHorizontalScrollMode(ScrollPerPixel);
        setVerticalScrollMode(ScrollPerPixel);
        frozenTableView->setVerticalScrollMode(ScrollPerPixel);
  }

  void FreezeTableWidget::updateSectionWidth(int logicalIndex, int /* oldSize */, int newSize)
  {
        if (logicalIndex == 0){
              frozenTableView->setColumnWidth(0, newSize);
              updateFrozenTableGeometry();
        }
  }

  void FreezeTableWidget::updateSectionHeight(int logicalIndex, int /* oldSize */, int newSize)
  {
        frozenTableView->setRowHeight(logicalIndex, newSize);
  }

  void FreezeTableWidget::resizeEvent(QResizeEvent * event)
  {
        QTableView::resizeEvent(event);
        updateFrozenTableGeometry();
   }

  QModelIndex FreezeTableWidget::moveCursor(CursorAction cursorAction,
                                            Qt::KeyboardModifiers modifiers)
  {
        QModelIndex current = QTableView::moveCursor(cursorAction, modifiers);

        if (cursorAction == MoveLeft && current.column() > 0
                && visualRect(current).topLeft().x() < frozenTableView->columnWidth(0) ){
              const int newValue = horizontalScrollBar()->value() + visualRect(current).topLeft().x()
                                   - frozenTableView->columnWidth(0);
              horizontalScrollBar()->setValue(newValue);
        }
        return current;
  }

  void FreezeTableWidget::scrollTo (const QModelIndex & index, ScrollHint hint){
      if (index.column() > 0)
          QTableView::scrollTo(index, hint);
  }

  void FreezeTableWidget::updateFrozenTableGeometry()
  {
        frozenTableView->setGeometry(verticalHeader()->width() + frameWidth(),
                                     frameWidth(), columnWidth(0),
                                     viewport()->height()+horizontalHeader()->height());
  }