- Qt 5.5
- Qt Widgets
- Painter Paths Example
- window.cpp Example File
- Qt 5.5.1 Reference Documentation

# window.cpp Example File

painting/painterpaths/window.cpp

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
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    #include "renderarea.h"
    #include "window.h"

    #include <QtWidgets>

    #include <cmath>

    const float Pi = 3.14159f;

    Window::Window()
    {
        QPainterPath rectPath;
        rectPath.moveTo(20.0, 30.0);
        rectPath.lineTo(80.0, 30.0);
        rectPath.lineTo(80.0, 70.0);
        rectPath.lineTo(20.0, 70.0);
        rectPath.closeSubpath();

        QPainterPath roundRectPath;
        roundRectPath.moveTo(80.0, 35.0);
        roundRectPath.arcTo(70.0, 30.0, 10.0, 10.0, 0.0, 90.0);
        roundRectPath.lineTo(25.0, 30.0);
        roundRectPath.arcTo(20.0, 30.0, 10.0, 10.0, 90.0, 90.0);
        roundRectPath.lineTo(20.0, 65.0);
        roundRectPath.arcTo(20.0, 60.0, 10.0, 10.0, 180.0, 90.0);
        roundRectPath.lineTo(75.0, 70.0);
        roundRectPath.arcTo(70.0, 60.0, 10.0, 10.0, 270.0, 90.0);
        roundRectPath.closeSubpath();

        QPainterPath ellipsePath;
        ellipsePath.moveTo(80.0, 50.0);
        ellipsePath.arcTo(20.0, 30.0, 60.0, 40.0, 0.0, 360.0);

        QPainterPath piePath;
        piePath.moveTo(50.0, 50.0);
        piePath.arcTo(20.0, 30.0, 60.0, 40.0, 60.0, 240.0);
        piePath.closeSubpath();

        QPainterPath polygonPath;
        polygonPath.moveTo(10.0, 80.0);
        polygonPath.lineTo(20.0, 10.0);
        polygonPath.lineTo(80.0, 30.0);
        polygonPath.lineTo(90.0, 70.0);
        polygonPath.closeSubpath();

        QPainterPath groupPath;
        groupPath.moveTo(60.0, 40.0);
        groupPath.arcTo(20.0, 20.0, 40.0, 40.0, 0.0, 360.0);
        groupPath.moveTo(40.0, 40.0);
        groupPath.lineTo(40.0, 80.0);
        groupPath.lineTo(80.0, 80.0);
        groupPath.lineTo(80.0, 40.0);
        groupPath.closeSubpath();

        QPainterPath textPath;
        QFont timesFont("Times", 50);
        timesFont.setStyleStrategy(QFont::ForceOutline);
        textPath.addText(10, 70, timesFont, tr("Qt"));

        QPainterPath bezierPath;
        bezierPath.moveTo(20, 30);
        bezierPath.cubicTo(80, 0, 50, 50, 80, 80);

        QPainterPath starPath;
        starPath.moveTo(90, 50);
        for (int i = 1; i < 5; ++i) {
            starPath.lineTo(50 + 40 * std::cos(0.8 * i * Pi),
                            50 + 40 * std::sin(0.8 * i * Pi));
        }
        starPath.closeSubpath();

        renderAreas.push_back(new RenderArea(rectPath));
        renderAreas.push_back(new RenderArea(roundRectPath));
        renderAreas.push_back(new RenderArea(ellipsePath));
        renderAreas.push_back(new RenderArea(piePath));
        renderAreas.push_back(new RenderArea(polygonPath));
        renderAreas.push_back(new RenderArea(groupPath));
        renderAreas.push_back(new RenderArea(textPath));
        renderAreas.push_back(new RenderArea(bezierPath));
        renderAreas.push_back(new RenderArea(starPath));

        fillRuleComboBox = new QComboBox;
        fillRuleComboBox->addItem(tr("Odd Even"), Qt::OddEvenFill);
        fillRuleComboBox->addItem(tr("Winding"), Qt::WindingFill);

        fillRuleLabel = new QLabel(tr("Fill &Rule:"));
        fillRuleLabel->setBuddy(fillRuleComboBox);

        fillColor1ComboBox = new QComboBox;
        populateWithColors(fillColor1ComboBox);
        fillColor1ComboBox->setCurrentIndex(fillColor1ComboBox->findText("mediumslateblue"));

        fillColor2ComboBox = new QComboBox;
        populateWithColors(fillColor2ComboBox);
        fillColor2ComboBox->setCurrentIndex(fillColor2ComboBox->findText("cornsilk"));

        fillGradientLabel = new QLabel(tr("&Fill Gradient:"));
        fillGradientLabel->setBuddy(fillColor1ComboBox);

        fillToLabel = new QLabel(tr("to"));
        fillToLabel->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);

        penWidthSpinBox = new QSpinBox;
        penWidthSpinBox->setRange(0, 20);

        penWidthLabel = new QLabel(tr("&Pen Width:"));
        penWidthLabel->setBuddy(penWidthSpinBox);

        penColorComboBox = new QComboBox;
        populateWithColors(penColorComboBox);
        penColorComboBox->setCurrentIndex(penColorComboBox->findText("darkslateblue"));

        penColorLabel = new QLabel(tr("Pen &Color:"));
        penColorLabel->setBuddy(penColorComboBox);

        rotationAngleSpinBox = new QSpinBox;
        rotationAngleSpinBox->setRange(0, 359);
        rotationAngleSpinBox->setWrapping(true);
        rotationAngleSpinBox->setSuffix(QLatin1String("\xB0"));

        rotationAngleLabel = new QLabel(tr("&Rotation Angle:"));
        rotationAngleLabel->setBuddy(rotationAngleSpinBox);

        connect(fillRuleComboBox, SIGNAL(activated(int)), this, SLOT(fillRuleChanged()));
        connect(fillColor1ComboBox, SIGNAL(activated(int)), this, SLOT(fillGradientChanged()));
        connect(fillColor2ComboBox, SIGNAL(activated(int)), this, SLOT(fillGradientChanged()));
        connect(penColorComboBox, SIGNAL(activated(int)), this, SLOT(penColorChanged()));

        for(QList<RenderArea*>::iterator it = renderAreas.begin(); it != renderAreas.end(); it++) {
            connect(penWidthSpinBox, SIGNAL(valueChanged(int)), *it, SLOT(setPenWidth(int)));
            connect(rotationAngleSpinBox, SIGNAL(valueChanged(int)), *it, SLOT(setRotationAngle(int)));
        }

        QGridLayout *topLayout = new QGridLayout;

        int i=0;
        for(QList<RenderArea*>::iterator it = renderAreas.begin(); it != renderAreas.end(); it++, i++)
            topLayout->addWidget(*it, i / 3, i % 3);

        QGridLayout *mainLayout = new QGridLayout;
        mainLayout->addLayout(topLayout, 0, 0, 1, 4);
        mainLayout->addWidget(fillRuleLabel, 1, 0);
        mainLayout->addWidget(fillRuleComboBox, 1, 1, 1, 3);
        mainLayout->addWidget(fillGradientLabel, 2, 0);
        mainLayout->addWidget(fillColor1ComboBox, 2, 1);
        mainLayout->addWidget(fillToLabel, 2, 2);
        mainLayout->addWidget(fillColor2ComboBox, 2, 3);
        mainLayout->addWidget(penWidthLabel, 3, 0);
        mainLayout->addWidget(penWidthSpinBox, 3, 1, 1, 3);
        mainLayout->addWidget(penColorLabel, 4, 0);
        mainLayout->addWidget(penColorComboBox, 4, 1, 1, 3);
        mainLayout->addWidget(rotationAngleLabel, 5, 0);
        mainLayout->addWidget(rotationAngleSpinBox, 5, 1, 1, 3);
        setLayout(mainLayout);

        fillRuleChanged();
        fillGradientChanged();
        penColorChanged();
        penWidthSpinBox->setValue(2);

        setWindowTitle(tr("Painter Paths"));
    }

    void Window::fillRuleChanged()
    {
        Qt::FillRule rule = (Qt::FillRule)currentItemData(fillRuleComboBox).toInt();

        for (QList<RenderArea*>::iterator it = renderAreas.begin(); it != renderAreas.end(); ++it)
            (*it)->setFillRule(rule);
    }

    void Window::fillGradientChanged()
    {
        QColor color1 = qvariant_cast<QColor>(currentItemData(fillColor1ComboBox));
        QColor color2 = qvariant_cast<QColor>(currentItemData(fillColor2ComboBox));

        for (QList<RenderArea*>::iterator it = renderAreas.begin(); it != renderAreas.end(); ++it)
            (*it)->setFillGradient(color1, color2);
    }

    void Window::penColorChanged()
    {
        QColor color = qvariant_cast<QColor>(currentItemData(penColorComboBox));

        for (QList<RenderArea*>::iterator it = renderAreas.begin(); it != renderAreas.end(); ++it)
            (*it)->setPenColor(color);
    }

    void Window::populateWithColors(QComboBox *comboBox)
    {
        QStringList colorNames = QColor::colorNames();
        foreach (QString name, colorNames)
            comboBox->addItem(name, QColor(name));
    }

    QVariant Window::currentItemData(QComboBox *comboBox)
    {
        return comboBox->itemData(comboBox->currentIndex());
    }