- Qt 5.5
- Qt Widgets
- Frozen Column Example
- freezetablewidget.cpp Example File
- Qt 5.5.1 Reference Documentation

# freezetablewidget.cpp Example File

itemviews/frozencolumn/freezetablewidget.cpp

    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
    ** You may use this file under the terms of the BSD license as follows:
    **
    ** "Redistribution and use in source and binary forms, with or without
    ** modification, are permitted provided that the following conditions are
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    **     from this software without specific prior written permission.
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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(),SIGNAL(sectionResized(int,int,int)), this,
                  SLOT(updateSectionWidth(int,int,int)));
          connect(verticalHeader(),SIGNAL(sectionResized(int,int,int)), this,
                  SLOT(updateSectionHeight(int,int,int)));

          connect(frozenTableView->verticalScrollBar(), SIGNAL(valueChanged(int)),
                  verticalScrollBar(), SLOT(setValue(int)));
          connect(verticalScrollBar(), SIGNAL(valueChanged(int)),
                  frozenTableView->verticalScrollBar(), SLOT(setValue(int)));

    }

    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());
    }