scribblearea.cpp Example File | Qt 4.8 (original) (raw)

widgets/scribble/scribblearea.cpp

#include

#include "scribblearea.h"

ScribbleArea::ScribbleArea(QWidget *parent) : QWidget(parent) { setAttribute(Qt::WA_StaticContents); modified = false; scribbling = false; myPenWidth = 1; myPenColor = Qt::blue; }

bool ScribbleArea::openImage(const QString &fileName) { QImage loadedImage; if (!loadedImage.load(fileName)) return false;

[QSize](qsize.html) newSize = loadedImage.size().expandedTo(size());
resizeImage(&loadedImage, newSize);
image = loadedImage;
modified = false;
update();
return true;

}

bool ScribbleArea::saveImage(const QString &fileName, const char *fileFormat) { QImage visibleImage = image; resizeImage(&visibleImage, size());

if (visibleImage.save(fileName, fileFormat)) {
    modified = false;
    return true;
} else {
    return false;
}

}

void ScribbleArea::setPenColor(const QColor &newColor) { myPenColor = newColor; }

void ScribbleArea::setPenWidth(int newWidth) { myPenWidth = newWidth; }

void ScribbleArea::clearImage() { image.fill(qRgb(255, 255, 255)); modified = true; update(); }

void ScribbleArea::mousePressEvent(QMouseEvent *event) { if (event->button() == Qt::LeftButton) { lastPoint = event->pos(); scribbling = true; } }

void ScribbleArea::mouseMoveEvent(QMouseEvent *event) { if ((event->buttons() & Qt::LeftButton) && scribbling) drawLineTo(event->pos()); }

void ScribbleArea::mouseReleaseEvent(QMouseEvent *event) { if (event->button() == Qt::LeftButton && scribbling) { drawLineTo(event->pos()); scribbling = false; } }

void ScribbleArea::paintEvent(QPaintEvent *event) { QPainter painter(this); QRect dirtyRect = event->rect(); painter.drawImage(dirtyRect, image, dirtyRect); }

void ScribbleArea::resizeEvent(QResizeEvent *event) { if (width() > image.width() || height() > image.height()) { int newWidth = qMax(width() + 128, image.width()); int newHeight = qMax(height() + 128, image.height()); resizeImage(&image, QSize(newWidth, newHeight)); update(); } QWidget::resizeEvent(event); }

void ScribbleArea::drawLineTo(const QPoint &endPoint) { QPainter painter(&image); painter.setPen(QPen(myPenColor, myPenWidth, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin)); painter.drawLine(lastPoint, endPoint); modified = true;

int rad = (myPenWidth / 2) + 2;
update([QRect](qrect.html)(lastPoint, endPoint).normalized()
                                 .adjusted(-rad, -rad, +rad, +rad));
lastPoint = endPoint;

}

void ScribbleArea::resizeImage(QImage *image, const QSize &newSize) { if (image->size() == newSize) return;

[QImage](qimage.html) newImage(newSize, [QImage](qimage.html)::Format_RGB32);
newImage.fill([qRgb](qcolor.html#qRgb)(255, 255, 255));
[QPainter](qpainter.html) painter(&newImage);
painter.drawImage([QPoint](qpoint.html)(0, 0), *image);
*image = newImage;

}

void ScribbleArea::print() { #ifndef QT_NO_PRINTER QPrinter printer(QPrinter::HighResolution);

[QPrintDialog](qprintdialog.html) *printDialog = new [QPrintDialog](qprintdialog.html)(&printer, this);
if (printDialog->exec() == [QDialog](qdialog.html)::Accepted) {
    [QPainter](qpainter.html) painter(&printer);
    [QRect](qrect.html) rect = painter.viewport();
    [QSize](qsize.html) size = image.size();
    size.scale(rect.size(), [Qt](qt-module.html)::KeepAspectRatio);
    painter.setViewport(rect.x(), rect.y(), size.width(), size.height());
    painter.setWindow(image.rect());
    painter.drawImage(0, 0, image);
}

#endif // QT_NO_PRINTER }

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