- Qt 5.5
- Qt Core
- Queued Custom Type Example
- window.cpp Example File
- Qt 5.5.1 Reference Documentation

# window.cpp Example File

threads/queuedcustomtype/window.cpp

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:BSD$
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    #include <QtWidgets>
    #include "window.h"

    Window::Window()
    {
        thread = new RenderThread();

        label = new QLabel();
        label->setAlignment(Qt::AlignCenter);

        loadButton = new QPushButton(tr("&Load image..."));
        resetButton = new QPushButton(tr("&Stop"));
        resetButton->setEnabled(false);

        connect(loadButton, SIGNAL(clicked()), this, SLOT(loadImage()));
        connect(resetButton, SIGNAL(clicked()), thread, SLOT(stopProcess()));
        connect(thread, SIGNAL(finished()), this, SLOT(resetUi()));
        connect(thread, SIGNAL(sendBlock(Block)), this, SLOT(addBlock(Block)));

        QHBoxLayout *buttonLayout = new QHBoxLayout();
        buttonLayout->addStretch();
        buttonLayout->addWidget(loadButton);
        buttonLayout->addWidget(resetButton);
        buttonLayout->addStretch();

        QVBoxLayout *layout = new QVBoxLayout(this);
        layout->addWidget(label);
        layout->addLayout(buttonLayout);

        setWindowTitle(tr("Queued Custom Type"));
    }

    void Window::loadImage()
    {
        QStringList formats;
        foreach (QByteArray format, QImageReader::supportedImageFormats())
            if (format.toLower() == format)
                formats.append("*." + format);

        QString newPath = QFileDialog::getOpenFileName(this, tr("Open Image"),
            path, tr("Image files (%1)").arg(formats.join(' ')));

        if (newPath.isEmpty())
            return;

        QImage image(newPath);
        if (!image.isNull()) {
            loadImage(image);
            path = newPath;
        }
    }

    void Window::loadImage(const QImage &image)
    {
        QDesktopWidget desktop;
        QImage useImage;
        QRect space = desktop.availableGeometry();
        if (image.width() > 0.75*space.width() || image.height() > 0.75*space.height())
            useImage = image.scaled(0.75*space.width(), 0.75*space.height(),
                                    Qt::KeepAspectRatio, Qt::SmoothTransformation);
        else
            useImage = image;

        pixmap = QPixmap(useImage.width(), useImage.height());
        pixmap.fill(qRgb(255, 255, 255));
        label->setPixmap(pixmap);
        loadButton->setEnabled(false);
        resetButton->setEnabled(true);
        thread->processImage(useImage);
    }

    void Window::addBlock(const Block &block)
    {
        QColor color = block.color();
        color.setAlpha(64);

        QPainter painter;
        painter.begin(&pixmap);
        painter.fillRect(block.rect(), color);
        painter.end();
        label->setPixmap(pixmap);
    }

    void Window::resetUi()
    {
        loadButton->setEnabled(true);
        resetButton->setEnabled(false);
    }