From 08c01f62593783b3c650e014a1112c0cd223710a Mon Sep 17 00:00:00 2001 From: Shawn Rutledge Date: Thu, 28 Dec 2023 19:15:14 -0700 Subject: [PATCH] Avoid crashing in the quickwidgets example after closing the subwindow Closing the window deletes m_quickWidget; so we disable the menu items for grabbing from it, because those cannot work. Also add asserts. Fixes: QTBUG-120296 Pick-to: 6.5 6.2 5.15 Change-Id: I68154c2d1e4553c771815e29cbe3b095d85893f1 Reviewed-by: Axel Spoerl (cherry picked from commit f719ee6408a92439a65e82abea4403df6a844066) Reviewed-by: Qt Cherry-pick Bot (cherry picked from commit a49d309b4acaba1dbb08ea1c554ad333b439b8cf) --- .../quick/quickwidgets/quickwidget/main.cpp | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/examples/quick/quickwidgets/quickwidget/main.cpp b/examples/quick/quickwidgets/quickwidget/main.cpp index ecac279a2f..584cecfb00 100644 --- a/examples/quick/quickwidgets/quickwidget/main.cpp +++ b/examples/quick/quickwidgets/quickwidget/main.cpp @@ -63,14 +63,22 @@ MainWindow::MainWindow() setCentralWidget(centralWidget); QMenu *fileMenu = menuBar()->addMenu(tr("&File")); - fileMenu->addAction(tr("Grab framebuffer"), this, &MainWindow::grabFramebuffer); - fileMenu->addAction(tr("Render to pixmap"), this, &MainWindow::renderToPixmap); - fileMenu->addAction(tr("Grab via grabToImage"), this, &MainWindow::grabToImage); + auto grabAction = fileMenu->addAction(tr("Grab framebuffer"), this, &MainWindow::grabFramebuffer); + auto renderAction = fileMenu->addAction(tr("Render to pixmap"), this, &MainWindow::renderToPixmap); + auto grabToImageAction = fileMenu->addAction(tr("Grab via grabToImage"), this, &MainWindow::grabToImage); fileMenu->addAction(tr("Quit"), qApp, &QCoreApplication::quit); QMenu *windowMenu = menuBar()->addMenu(tr("&Window")); windowMenu->addAction(tr("Add tab widget"), this, [this, centralWidget] { createQuickWidgetsInTabs(centralWidget); }); + + connect(m_quickWidget, &QObject::destroyed, this, + [this, grabAction, renderAction, grabToImageAction] { + m_quickWidget = nullptr; + grabAction->setEnabled(false); + renderAction->setEnabled(false); + grabToImageAction->setEnabled(false); + }); } void MainWindow::createQuickWidgetsInTabs(QMdiArea *mdiArea) @@ -123,6 +131,7 @@ void MainWindow::quickWidgetStatusChanged(QQuickWidget::Status status) { if (status == QQuickWidget::Error) { QStringList errors; + Q_ASSERT(m_quickWidget); const auto widgetErrors = m_quickWidget->errors(); for (const QQmlError &error : widgetErrors) errors.append(error.toString()); @@ -147,12 +156,14 @@ template void saveToFile(QWidget *parent, T *saveable) void MainWindow::grabFramebuffer() { + Q_ASSERT(m_quickWidget); QImage image = m_quickWidget->grabFramebuffer(); saveToFile(this, &image); } void MainWindow::renderToPixmap() { + Q_ASSERT(m_quickWidget); QPixmap pixmap(m_quickWidget->size()); m_quickWidget->render(&pixmap); saveToFile(this, &pixmap); @@ -165,6 +176,7 @@ void MainWindow::grabToImage() fd.setDefaultSuffix("png"); fd.selectFile("test_grabToImage.png"); if (fd.exec() == QDialog::Accepted) { + Q_ASSERT(m_quickWidget); QMetaObject::invokeMethod(m_quickWidget->rootObject(), "performLayerBasedGrab", Q_ARG(QVariant, fd.selectedFiles().first())); }