CheckboxDelegate.cpp

/**
 * \file
 * \author Lars Bilke
 * \date   2010-08-19
 * \brief  Implementation of the CheckboxDelegate class.
 *
 * \copyright
 * Copyright (c) 2013, OpenGeoSys Community (http://www.opengeosys.org)
 *            Distributed under a Modified BSD License.
 *              See accompanying file LICENSE.txt or
 *              http://www.opengeosys.org/project/license
 *
 */

// ** INCLUDES **
#include "CheckboxDelegate.h"
#include <QApplication>
#include <QCheckBox>
#include <QEvent>
#include <QMouseEvent>
#include <QPainter>
#include <QStyleOptionButton>

#include <iostream>

CheckboxDelegate::CheckboxDelegate(QObject* parent)
	: QItemDelegate(parent)
{
}

void CheckboxDelegate::paint(QPainter* painter, const QStyleOptionViewItem& option,
                             const QModelIndex& index) const
{
	if(index.isValid())
	{
		bool checked = index.model()->data(index, Qt::DisplayRole).toBool();

		QStyleOptionButton styleOptionButton;
		styleOptionButton.state |= QStyle::State_Enabled;
		if (checked)
			styleOptionButton.state |= QStyle::State_On;
		else
			styleOptionButton.state |= QStyle::State_Off;

		styleOptionButton.rect = this->checkboxRect(option);

		QApplication::style()->drawControl(QStyle::CE_CheckBox,
		                                   &styleOptionButton, painter);
	}
	else
		QItemDelegate::paint(painter, option, index);
}

bool CheckboxDelegate::editorEvent(QEvent* event, QAbstractItemModel* model,
                                   const QStyleOptionViewItem &option, const QModelIndex &index)
{
	Q_UNUSED(option);

	if ((event->type() == QEvent::MouseButtonRelease) ||
	    (event->type() == QEvent::MouseButtonDblClick))
	{
		QMouseEvent* mouse_event = static_cast<QMouseEvent*>(event);
		if (mouse_event->button() != Qt::LeftButton ||
		    !checkboxRect(option).contains(mouse_event->pos()))
			return false;
		if (event->type() == QEvent::MouseButtonDblClick)
			return true;
	}
	else if (event->type() == QEvent::KeyPress)
	{
		if (static_cast<QKeyEvent*>(event)->key() != Qt::Key_Space &&
		    static_cast<QKeyEvent*>(event)->key() != Qt::Key_Select)
			return false;
	}
	else
		return false;

	bool checked = index.model()->data(index, Qt::DisplayRole).toBool();
	return model->setData(index, !checked, Qt::EditRole);
}

QSize CheckboxDelegate::sizeHint(const QStyleOptionViewItem & option,
                                 const QModelIndex & index) const
{
	Q_UNUSED(index);

	QRect rect = checkboxRect(option);
	return QSize(rect.width(), rect.height());
}

QRect CheckboxDelegate::checkboxRect(const QStyleOptionViewItem& viewItemStyleOptions) const
{
	QStyleOptionButton styleOptionButton;
	QRect rect = QApplication::style()->subElementRect(
	        QStyle::SE_CheckBoxIndicator, &styleOptionButton);
	QPoint point(viewItemStyleOptions.rect.x() +
	             viewItemStyleOptions.rect.width() / 2 - rect.width() / 2,
	             viewItemStyleOptions.rect.y() + viewItemStyleOptions.rect.height() / 2 -
	             rect.height() / 2);
	return QRect(point, rect.size());
}