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// Copyright (C) 2024 Christian Ehrlicher <ch.ehrlicher@gmx.de>
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include <QPaintEvent>
#include <QPainter>
#include <QPainterStateGuard>
#include <QWidget>
namespace src_gui_painting_qpainterstateguard {
struct MyWidget : public QWidget
{
void paintEvent(QPaintEvent *) override;
bool drawText = true;
QLine line;
};
struct MyGuardWidget : public QWidget
{
void paintEvent(QPaintEvent *) override;
bool drawText = true;
QLine line;
};
//! [0]
void MyWidget::paintEvent(QPaintEvent *)
{
QPainter painter(this);
painter.setPen(Qt::red);
if (drawText) {
painter.save();
painter.setPen(Qt::blue);
painter.setFont(QFont("Arial", 30));
painter.drawText(rect(), Qt::AlignCenter, "Qt");
painter.restore(); // don't forget to restore previous painter state
}
painter.drawLine(line);
}
//! [0]
//! [1]
void MyGuardWidget::paintEvent(QPaintEvent *)
{
QPainter painter(this);
painter.setPen(Qt::red);
if (drawText) {
QPainterStateGuard guard(&painter);
painter.setPen(Qt::blue);
painter.setFont(QFont("Arial", 30));
painter.drawText(rect(), Qt::AlignCenter, "Qt");
}
painter.drawLine(line);
}
//! [1]
} // src_gui_painting_qpainterstateguard