character painter widget : QFont « Qt « C++






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();
}

   
    
  








Related examples in the same category

1.Create QFont
2.plain text layout