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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "scribblearea.h"
#include <QMouseEvent>
#include <QPainter>
#if defined(QT_PRINTSUPPORT_LIB)
#include <QtPrintSupport/qtprintsupportglobal.h>
#if QT_CONFIG(printdialog)
#include <QPrinter>
#include <QPrintDialog>
#endif
#endif
//! [0]
ScribbleArea::ScribbleArea(QWidget *parent)
: QWidget(parent)
{
setAttribute(Qt::WA_StaticContents);
}
//! [0]
//! [1]
bool ScribbleArea::openImage(const QString &fileName)
//! [1] //! [2]
{
QImage loadedImage;
if (!loadedImage.load(fileName))
return false;
QSize newSize = loadedImage.size().expandedTo(size());
resizeImage(&loadedImage, newSize);
image = loadedImage;
modified = false;
update();
return true;
}
//! [2]
//! [3]
bool ScribbleArea::saveImage(const QString &fileName, const char *fileFormat)
//! [3] //! [4]
{
QImage visibleImage = image;
resizeImage(&visibleImage, size());
if (visibleImage.save(fileName, fileFormat)) {
modified = false;
return true;
}
return false;
}
//! [4]
//! [5]
void ScribbleArea::setPenColor(const QColor &newColor)
//! [5] //! [6]
{
myPenColor = newColor;
}
//! [6]
//! [7]
void ScribbleArea::setPenWidth(int newWidth)
//! [7] //! [8]
{
myPenWidth = newWidth;
}
//! [8]
//! [9]
void ScribbleArea::clearImage()
//! [9] //! [10]
{
image.fill(qRgb(255, 255, 255));
modified = true;
update();
}
//! [10]
//! [11]
void ScribbleArea::mousePressEvent(QMouseEvent *event)
//! [11] //! [12]
{
if (event->button() == Qt::LeftButton) {
lastPoint = event->position().toPoint();
scribbling = true;
}
}
void ScribbleArea::mouseMoveEvent(QMouseEvent *event)
{
if ((event->buttons() & Qt::LeftButton) && scribbling)
drawLineTo(event->position().toPoint());
}
void ScribbleArea::mouseReleaseEvent(QMouseEvent *event)
{
if (event->button() == Qt::LeftButton && scribbling) {
drawLineTo(event->position().toPoint());
scribbling = false;
}
}
//! [12] //! [13]
void ScribbleArea::paintEvent(QPaintEvent *event)
//! [13] //! [14]
{
QPainter painter(this);
QRect dirtyRect = event->rect();
painter.drawImage(dirtyRect, image, dirtyRect);
}
//! [14]
//! [15]
void ScribbleArea::resizeEvent(QResizeEvent *event)
//! [15] //! [16]
{
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);
}
//! [16]
//! [17]
void ScribbleArea::drawLineTo(const QPoint &endPoint)
//! [17] //! [18]
{
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(lastPoint, endPoint).normalized()
.adjusted(-rad, -rad, +rad, +rad));
lastPoint = endPoint;
}
//! [18]
//! [19]
void ScribbleArea::resizeImage(QImage *image, const QSize &newSize)
//! [19] //! [20]
{
if (image->size() == newSize)
return;
QImage newImage(newSize, QImage::Format_RGB32);
newImage.fill(qRgb(255, 255, 255));
QPainter painter(&newImage);
painter.drawImage(QPoint(0, 0), *image);
*image = newImage;
}
//! [20]
//! [21]
void ScribbleArea::print()
{
#if defined(QT_PRINTSUPPORT_LIB) && QT_CONFIG(printdialog)
QPrinter printer(QPrinter::HighResolution);
QPrintDialog printDialog(&printer, this);
//! [21] //! [22]
if (printDialog.exec() == QDialog::Accepted) {
QPainter painter(&printer);
QRect rect = painter.viewport();
QSize size = image.size();
size.scale(rect.size(), Qt::KeepAspectRatio);
painter.setViewport(rect.x(), rect.y(), size.width(), size.height());
painter.setWindow(image.rect());
painter.drawImage(0, 0, image);
}
#endif // QT_CONFIG(printdialog)
}
//! [22]
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