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character painter widget

 
 
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef CHARACTERWIDGET_H
#define CHARACTERWIDGET_H
#include <QFont>
#include <QPoint>
#include <QSize>
#include <QString>
#include <QWidget>
QT_BEGIN_NAMESPACE
class QMouseEvent;
class QPaintEvent;
QT_END_NAMESPACE
 
class CharacterWidget : public QWidget
{
    Q_OBJECT
public:
    CharacterWidget(QWidget *parent = 0);
    QSize sizeHint() const;
public slots:
    void updateFont(const QFont &font);
    void updateSize(const QString &fontSize);
    void updateStyle(const QString &fontStyle);
    void updateFontMerging(bool enable);
signals:
    void characterSelected(const QString &character);
protected:
    void mouseMoveEvent(QMouseEvent *event);
    void mousePressEvent(QMouseEvent *event);
    void paintEvent(QPaintEvent *event);
private:
    QFont displayFont;
    int columns;
    int lastKey;
    int squareSize;
};
 
#endif
 
 
#include <QtGui>
#include "characterwidget.h"
 
CharacterWidget::CharacterWidget(QWidget *parent)
    : QWidget(parent)
{
    squareSize = 24;
    columns = 16;
    lastKey = -1;
    setMouseTracking(true);
}
 
void CharacterWidget::updateFont(const QFont &font)
{
    displayFont.setFamily(font.family());
    squareSize = qMax(24, QFontMetrics(displayFont).xHeight() * 3);
    adjustSize();
    update();
}
 
void CharacterWidget::updateSize(const QString &fontSize)
{
    displayFont.setPointSize(fontSize.toInt());
    squareSize = qMax(24, QFontMetrics(displayFont).xHeight() * 3);
    adjustSize();
    update();
}
 
void CharacterWidget::updateStyle(const QString &fontStyle)
{
    QFontDatabase fontDatabase;
    const QFont::StyleStrategy oldStrategy = displayFont.styleStrategy();
    displayFont = fontDatabase.font(displayFont.family(), fontStyle, displayFont.pointSize());
    displayFont.setStyleStrategy(oldStrategy);
    squareSize = qMax(24, QFontMetrics(displayFont).xHeight() * 3);
    adjustSize();
    update();
}
void CharacterWidget::updateFontMerging(bool enable)
{
    if (enable)
        displayFont.setStyleStrategy(QFont::PreferDefault);
    else
        displayFont.setStyleStrategy(QFont::NoFontMerging);
    adjustSize();
    update();
}
 
QSize CharacterWidget::sizeHint() const
{
    return QSize(columns*squareSize, (65536/columns)*squareSize);
}
 
void CharacterWidget::mouseMoveEvent(QMouseEvent *event)
{
    QPoint widgetPosition = mapFromGlobal(event->globalPos());
    uint key = (widgetPosition.y()/squareSize)*columns + widgetPosition.x()/squareSize;
    QString text = QString::fromLatin1("<p>Character: <span style=\"font-size: 24pt; font-family: %1\">").arg(displayFont.family())
                  + QChar(key)
                  + QString::fromLatin1("</span><p>Value: 0x")
                  + QString::number(key, 16);
    QToolTip::showText(event->globalPos(), text, this);
}
 
void CharacterWidget::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        lastKey = (event->y()/squareSize)*columns + event->x()/squareSize;
        if (QChar(lastKey).category() != QChar::NoCategory)
            emit characterSelected(QString(QChar(lastKey)));
        update();
    }
    else
        QWidget::mousePressEvent(event);
}
 
void CharacterWidget::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    painter.fillRect(event->rect(), QBrush(Qt::white));
    painter.setFont(displayFont);
 
    QRect redrawRect = event->rect();
    int beginRow = redrawRect.top()/squareSize;
    int endRow = redrawRect.bottom()/squareSize;
    int beginColumn = redrawRect.left()/squareSize;
    int endColumn = redrawRect.right()/squareSize;
 
    painter.setPen(QPen(Qt::gray));
    for (int row = beginRow; row <= endRow; ++row) {
        for (int column = beginColumn; column <= endColumn; ++column) {
            painter.drawRect(column*squareSize, row*squareSize, squareSize, squareSize);
        }
 
    }
 
    QFontMetrics fontMetrics(displayFont);
    painter.setPen(QPen(Qt::black));
    for (int row = beginRow; row <= endRow; ++row) {
        for (int column = beginColumn; column <= endColumn; ++column) {
            int key = row*columns + column;
            painter.setClipRect(column*squareSize, row*squareSize, squareSize, squareSize);
            if (key == lastKey)
                painter.fillRect(column*squareSize + 1, row*squareSize + 1, squareSize, squareSize, QBrush(Qt::red));
            painter.drawText(column*squareSize + (squareSize / 2) - fontMetrics.width(QChar(key))/2,
                             row*squareSize + 4 + fontMetrics.ascent(),
                             QString(QChar(key)));
        }
    }
}
 
 
 
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QString>
QT_BEGIN_NAMESPACE
class QClipboard;
class QComboBox;
class QFontComboBox;
class QLineEdit;
class QScrollArea;
class QCheckBox;
QT_END_NAMESPACE
class CharacterWidget;
 
class MainWindow : public QMainWindow
{
    Q_OBJECT
public:
    MainWindow();
public slots:
    void findStyles(const QFont &font);
    void findSizes(const QFont &font);
    void insertCharacter(const QString &character);
    void updateClipboard();
private:
    CharacterWidget *characterWidget;
    QClipboard *clipboard;
    QComboBox *styleCombo;
    QComboBox *sizeCombo;
    QFontComboBox *fontCombo;
    QLineEdit *lineEdit;
    QScrollArea *scrollArea;
    QCheckBox *fontMerging;
};
 
#endif
 
 
 
#include <QtGui>
#include "characterwidget.h"
#include "mainwindow.h"
 
MainWindow::MainWindow()
{
    QWidget *centralWidget = new QWidget;
    QLabel *fontLabel = new QLabel(tr("Font:"));
    fontCombo = new QFontComboBox;
    QLabel *sizeLabel = new QLabel(tr("Size:"));
    sizeCombo = new QComboBox;
    QLabel *styleLabel = new QLabel(tr("Style:"));
    styleCombo = new QComboBox;
    QLabel *fontMergingLabel = new QLabel(tr("Automatic Font Merging:"));
    fontMerging = new QCheckBox;
    fontMerging->setChecked(true);
    scrollArea = new QScrollArea;
    characterWidget = new CharacterWidget;
    scrollArea->setWidget(characterWidget);
 
    findStyles(fontCombo->currentFont());
    findSizes(fontCombo->currentFont());
 
    lineEdit = new QLineEdit;
    QPushButton *clipboardButton = new QPushButton(tr("&To clipboard"));
 
    clipboard = QApplication::clipboard();
 
    connect(fontCombo, SIGNAL(currentFontChanged(const QFont &)),
            this, SLOT(findStyles(const QFont &)));
    connect(fontCombo, SIGNAL(currentFontChanged(const QFont &)),
            this, SLOT(findSizes(const QFont &)));
    connect(fontCombo, SIGNAL(currentFontChanged(const QFont &)),
            characterWidget, SLOT(updateFont(const QFont &)));
    connect(sizeCombo, SIGNAL(currentIndexChanged(const QString &)),
            characterWidget, SLOT(updateSize(const QString &)));
    connect(styleCombo, SIGNAL(currentIndexChanged(const QString &)),
            characterWidget, SLOT(updateStyle(const QString &)));
 
    connect(characterWidget, SIGNAL(characterSelected(const QString &)),
            this, SLOT(insertCharacter(const QString &)));
    connect(clipboardButton, SIGNAL(clicked()), this, SLOT(updateClipboard()));
    connect(fontMerging, SIGNAL(toggled(bool)), characterWidget, SLOT(updateFontMerging(bool)));
 
    QHBoxLayout *controlsLayout = new QHBoxLayout;
    controlsLayout->addWidget(fontLabel);
    controlsLayout->addWidget(fontCombo, 1);
    controlsLayout->addWidget(sizeLabel);
    controlsLayout->addWidget(sizeCombo, 1);
    controlsLayout->addWidget(styleLabel);
    controlsLayout->addWidget(styleCombo, 1);
    controlsLayout->addWidget(fontMergingLabel);
    controlsLayout->addWidget(fontMerging, 1);
    controlsLayout->addStretch(1);
    QHBoxLayout *lineLayout = new QHBoxLayout;
    lineLayout->addWidget(lineEdit, 1);
    lineLayout->addSpacing(12);
    lineLayout->addWidget(clipboardButton);
    QVBoxLayout *centralLayout = new QVBoxLayout;
    centralLayout->addLayout(controlsLayout);
    centralLayout->addWidget(scrollArea, 1);
    centralLayout->addSpacing(4);
    centralLayout->addLayout(lineLayout);
    centralWidget->setLayout(centralLayout);
    setCentralWidget(centralWidget);
    setWindowTitle(tr("Character Map"));
}
 
void MainWindow::findStyles(const QFont &font)
{
    QFontDatabase fontDatabase;
    QString currentItem = styleCombo->currentText();
    styleCombo->clear();
 
    QString style;
    foreach (style, fontDatabase.styles(font.family()))
        styleCombo->addItem(style);
    int styleIndex = styleCombo->findText(currentItem);
    if (styleIndex == -1)
        styleCombo->setCurrentIndex(0);
    else
        styleCombo->setCurrentIndex(styleIndex);
}
 
void MainWindow::findSizes(const QFont &font)
{
    QFontDatabase fontDatabase;
    QString currentSize = sizeCombo->currentText();
    sizeCombo->blockSignals(true);
    sizeCombo->clear();
    int size;
    if(fontDatabase.isSmoothlyScalable(font.family(), fontDatabase.styleString(font))) {
        foreach(size, QFontDatabase::standardSizes()) {
            sizeCombo->addItem(QVariant(size).toString());
            sizeCombo->setEditable(true);
        }
    } else {
        foreach(size, fontDatabase.smoothSizes(font.family(), fontDatabase.styleString(font))) {
            sizeCombo->addItem(QVariant(size).toString());
            sizeCombo->setEditable(false);
        }
    }
    sizeCombo->blockSignals(false);
    int sizeIndex = sizeCombo->findText(currentSize);
    if(sizeIndex == -1)
        sizeCombo->setCurrentIndex(qMax(0, sizeCombo->count() / 3));
    else
        sizeCombo->setCurrentIndex(sizeIndex);
}
 
void MainWindow::insertCharacter(const QString &character)
{
    lineEdit->insert(character);
}
 
void MainWindow::updateClipboard()
{
    clipboard->setText(lineEdit->text(), QClipboard::Clipboard);
    clipboard->setText(lineEdit->text(), QClipboard::Selection);
}
 
 
 
#include <QApplication>
#include "mainwindow.h"
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    MainWindow window;
    window.show();
    return app.exec();
}


Create QFont

 
Foundations of Qt Development\Chapter07\paths\main.cpp
/*
 * Copyright (c) 2006-2007, Johan Thelin
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright notice, 
 *       this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright notice,  
 *       this list of conditions and the following disclaimer in the documentation 
 *       and/or other materials provided with the distribution.
 *     * Neither the name of APress nor the names of its contributors 
 *       may be used to endorse or promote products derived from this software 
 *       without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
#include <QApplication>
#include <QPainter>
#include <QPainterPath>
#include <QPixmap>
int main( int argc, char **argv )
{
  QApplication app( argc, argv );
 
  QPixmap pixmap( 200, 200 );
  pixmap.fill( Qt::white );
 
  QPainterPath path;
 
  path.addEllipse( 80, 80, 80, 80 );
 
  path.moveTo( 120, 120 );
  path.lineTo( 120, 40 );
  path.arcTo( 40, 40, 160, 160, 90, 90 );
  path.lineTo( 120, 120 );
 
  QFont font = QApplication::font();
  font.setPixelSize( 40 );
 
  path.addText( 20, 180, font, "Path" );
 
  QPainter painter( &pixmap );
  painter.setRenderHint( QPainter::Antialiasing );
 
  painter.setPen( Qt::black );
  painter.setBrush( Qt::gray );
 
  painter.drawPath( path );
 
  pixmap.save( "path.png" );
 
  return 0;
}


Font dialog demo

 
 
Chapter03\colorandfont\main.cpp
/*
 * Copyright (c) 2006-2007, Johan Thelin
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 * 
 *     * Redistributions of source code must retain the above copyright notice, 
 *       this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright notice,  
 *       this list of conditions and the following disclaimer in the documentation 
 *       and/or other materials provided with the distribution.
 *     * Neither the name of APress nor the names of its contributors 
 *       may be used to endorse or promote products derived from this software 
 *       without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
#include <QApplication>
#include <QFontDialog>
#include <QColorDialog>
class Tester : public QWidget
{
public:
  void doColor()
  {
    QColor color = QColorDialog::getColor(Qt::yellow, this );
    if( color.isValid() )
    {
      qDebug( "ok" );
    }
  }
 
  void doFont()
  {
    bool ok;
    QFont font = QFontDialog::getFont( 
                    &ok, 
                    QFont( "Arial", 18 ), 
                    this, 
                    tr("Pick a font") );
    if( ok )
    {
      qDebug( "ok" );
    }
  }
};
int main( int argc, char **argv )
{
  QApplication app( argc, argv );
 
  Tester t;
  t.doColor();
  t.doFont();
 
  return 0;
}


plain text layout

 
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef WINDOW_H
#define WINDOW_H
#include <QWidget>
class Window : public QWidget
{
    Q_OBJECT
public:
    Window(QWidget *parent = 0);
protected:
    void paintEvent(QPaintEvent *event);
private:
    QFont font;
    QString text;
};
#endif
 
 
#include <QtGui>
#include <math.h>
#include "window.h"
Window::Window(QWidget *parent)
    : QWidget(parent)
{
    text = QString("Support for text rendering and layout in Qt 4 has been "
                   "redesigned around a system that allows textual content to "
                   "be represented in a more flexible way than was possible "
                   "with Qt 3. Qt 4 also provides a more convenient "
                   "programming interface for editing documents. These "
                   "improvements are made available through a reimplementation "
                   "of the existing text rendering engine, and the "
                   "introduction of several new classes. "
                   "See the relevant module overview for a detailed discussion "
                   "of this framework. The following sections provide a brief "
                   "overview of the main concepts behind Scribe.");
    setWindowTitle(tr("Plain Text Layout"));
}
void Window::paintEvent(QPaintEvent *event)
{
    QTextLayout textLayout(text, font);
    qreal margin = 10;
    qreal radius = qMin(width()/2.0, height()/2.0) - margin;
    QFontMetrics fm(font);
    qreal lineHeight = fm.height();
    qreal y = 0;
    textLayout.beginLayout();
    while (1) {
        // create a new line 
        QTextLine line = textLayout.createLine();
        if (!line.isValid())
            break;
        qreal x1 = qMax(0.0, pow(pow(radius,2)-pow(radius-y,2), 0.5));
        qreal x2 = qMax(0.0, pow(pow(radius,2)-pow(radius-(y+lineHeight),2), 0.5));
        qreal x = qMax(x1, x2) + margin;
        qreal lineWidth = (width() - margin) - x;
        line.setLineWidth(lineWidth);
        line.setPosition(QPointF(x, margin+y));
        y += line.height();
    }
    textLayout.endLayout();
    QPainter painter;
    painter.begin(this);
    painter.setRenderHint(QPainter::Antialiasing);
    painter.fillRect(rect(), Qt::white);
    painter.setBrush(QBrush(Qt::black));
    painter.setPen(QPen(Qt::black));
    textLayout.draw(&painter, QPoint(0,0));
    painter.setBrush(QBrush(QColor("#a6ce39")));
    painter.setPen(QPen(Qt::black));
    painter.drawEllipse(QRectF(-radius, margin, 2*radius, 2*radius));
    painter.end();
}
 
 
#include <QtGui>
#include "window.h"
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Window *window = new Window;
    window->resize(337, 343);
    window->show();
    return app.exec();
}


QFontDatabase and QTreeWidget

 
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
int main(int argc, char **argv)
{
    QApplication app(argc, argv);
 
    QFontDatabase database;
    QTreeWidget fontTree;
    fontTree.setColumnCount(2);
    fontTree.setHeaderLabels(QStringList() << "Font" << "Smooth Sizes");
    foreach (QString family, database.families()) {
        QTreeWidgetItem *familyItem = new QTreeWidgetItem(&fontTree);
        familyItem->setText(0, family);
        foreach (QString style, database.styles(family)) {
            QTreeWidgetItem *styleItem = new QTreeWidgetItem(familyItem);
            styleItem->setText(0, style);
            QString sizes;
            foreach (int points, database.smoothSizes(family, style))
                sizes += QString::number(points) + " ";
            styleItem->setText(1, sizes.trimmed());
        }
 
    }
 
    fontTree.resizeColumnToContents(0);
    fontTree.show();
    return app.exec();
}
Источник — «http://cppe.ru/index.php/C%2B%2B/Qt»