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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QtWidgets>
#if defined(QT_PRINTSUPPORT_LIB)
#include <QtPrintSupport/qtprintsupportglobal.h>
#if QT_CONFIG(printdialog)
#include <QPrinter>
#include <QPrintDialog>
#endif
#endif
#include "scribblearea.h"
static const qreal MinimumDiameter = 3.0;
static const qreal MaximumDiameter = 50.0;
//! [0]
ScribbleArea::ScribbleArea(QWidget *parent)
: QWidget(parent)
{
setAttribute(Qt::WA_AcceptTouchEvents);
setAttribute(Qt::WA_StaticContents);
modified = false;
myPenColors
<< QColor("green")
<< QColor("purple")
<< QColor("red")
<< QColor("blue")
<< QColor("yellow")
<< QColor("pink")
<< QColor("orange")
<< QColor("brown")
<< QColor("grey")
<< QColor("black");
}
//! [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;
} else {
return false;
}
}
//! [4]
//! [9]
void ScribbleArea::clearImage()
//! [9] //! [10]
{
image.fill(qRgb(255, 255, 255));
modified = true;
update();
}
//! [10]
//! [12] //! [13]
void ScribbleArea::paintEvent(QPaintEvent *event)
//! [13] //! [14]
{
QPainter painter(this);
const QRect rect = event->rect();
painter.drawImage(rect.topLeft(), image, rect);
}
//! [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]
//! [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]
bool ScribbleArea::event(QEvent *event)
{
switch (event->type()) {
case QEvent::TouchBegin:
case QEvent::TouchUpdate:
case QEvent::TouchEnd:
{
const QTouchEvent *touch = static_cast<QTouchEvent *>(event);
const auto touchPoints = static_cast<QTouchEvent *>(event)->points();
for (const QTouchEvent::TouchPoint &touchPoint : touchPoints) {
switch (touchPoint.state()) {
case QEventPoint::Stationary:
case QEventPoint::Released:
// don't do anything if this touch point hasn't moved or has been released
continue;
default:
{
QSizeF diams = touchPoint.ellipseDiameters();
if (diams.isEmpty()) {
qreal diameter = MaximumDiameter;
if (touch->pointingDevice()->capabilities().testFlag(QPointingDevice::Capability::Pressure))
diameter = MinimumDiameter + (MaximumDiameter - MinimumDiameter) * touchPoint.pressure();
diams = QSizeF(diameter, diameter);
}
QPainter painter(&image);
painter.setPen(Qt::NoPen);
painter.setBrush(myPenColors.at(touchPoint.id() % myPenColors.count()));
painter.drawEllipse(touchPoint.position(), diams.width() / 2, diams.height() / 2);
painter.end();
modified = true;
const int rad = 2;
QRectF rect(QPointF(), diams);
rect.moveCenter(touchPoint.position());
update(rect.toRect().adjusted(-rad,-rad, +rad, +rad));
}
break;
}
}
break;
}
default:
return QWidget::event(event);
}
return true;
}
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