path: root/src/widgets/kernel/qwindowcontainer.cpp

// Copyright (C) 2016 The Qt Company Ltd.// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only#include"qwindowcontainer_p.h"#include"qwidget_p.h"#include"qwidgetwindow_p.h"#include <QtGui/qwindow.h>#include <QtGui/private/qwindow_p.h>#include <QtGui/private/qguiapplication_p.h>#include <qpa/qplatformintegration.h>#include <QDebug>#if QT_CONFIG(mdiarea)#include <QMdiSubWindow>#endif#include <QAbstractScrollArea>#include <QPainter>#include <QtCore/qpointer.h> QT_BEGIN_NAMESPACE using namespaceQt::StringLiterals;class QWindowContainerPrivate :public QWidgetPrivate {public:Q_DECLARE_PUBLIC(QWindowContainer)QWindowContainerPrivate():window(nullptr),usesNativeWidgets(false){}~QWindowContainerPrivate() { }static QWindowContainerPrivate *get(QWidget *w) { QWindowContainer *wc = qobject_cast<QWindowContainer *>(w);if(wc)return wc->d_func();returnnullptr;}voidupdateGeometry() {Q_Q(QWindowContainer);if(!q->isWindow() && (q->geometry().bottom() <=0|| q->geometry().right() <=0))/* Qt (e.g. QSplitter) sometimes prefer to hide a widget by *not* calling setVisible(false). This is often done by setting its coordinates to a sufficiently negative value so that its clipped outside the parent. Since a QWindow is not clipped to widgets in general, it needs to be dealt with as a special case. */ window->setGeometry(q->geometry());else if(usesNativeWidgets) window->setGeometry(q->rect());else window->setGeometry(QRect(q->mapTo(q->window(),QPoint()), q->size()));}voidupdateUsesNativeWidgets(){if(window->parent() ==nullptr)return;Q_Q(QWindowContainer);if(q->testAttribute(Qt::WA_DontCreateNativeAncestors))return;if(q->internalWinId()) {// Allow use native widgets if the window container is already a native widget usesNativeWidgets =true;return;}bool nativeWidgetSet =false; QWidget *p = q->parentWidget();while(p) {if(false#if QT_CONFIG(mdiarea)|| qobject_cast<QMdiSubWindow *>(p) !=0#endif#if QT_CONFIG(scrollarea)|| qobject_cast<QAbstractScrollArea *>(p) !=0#endif) { q->winId(); nativeWidgetSet =true;break;} p = p->parentWidget();} usesNativeWidgets = nativeWidgetSet;}voidmarkParentChain() {Q_Q(QWindowContainer); QWidget *p = q;while(p) { QWidgetPrivate *d =static_cast<QWidgetPrivate *>(QWidgetPrivate::get(p)); d->createExtra(); d->extra->hasWindowContainer =true; p = p->parentWidget();}}boolisStillAnOrphan()const{return window->parent() == &fakeParent;} QPointer<QWindow> window; QWindow fakeParent; uint usesNativeWidgets :1;};/*! \fn QWidget *QWidget::createWindowContainer(QWindow *window, QWidget *parent, Qt::WindowFlags flags); Creates a QWidget that makes it possible to embed \a window into a QWidget-based application. The window container is created as a child of \a parent and with window flags \a flags. Once the window has been embedded into the container, the container will control the window's geometry and visibility. Explicit calls to QWindow::setGeometry(), QWindow::show() or QWindow::hide() on an embedded window is not recommended. The container takes over ownership of \a window. The window can be removed from the window container with a call to QWindow::setParent(). The window container is attached as a native child window to the toplevel window it is a child of. When a window container is used as a child of a QAbstractScrollArea or QMdiArea, it will create a \l {Native Widgets vs Alien Widgets} {native window} for every widget in its parent chain to allow for proper stacking and clipping in this use case. Creating a native window for the window container also allows for proper stacking and clipping. This must be done before showing the window container. Applications with many native child windows may suffer from performance issues. The window container has a number of known limitations: \list \li Stacking order; The embedded window will stack on top of the widget hierarchy as an opaque box. The stacking order of multiple overlapping window container instances is undefined. \li Rendering Integration; The window container does not interoperate with QGraphicsProxyWidget, QWidget::render() or similar functionality. \li Focus Handling; It is possible to let the window container instance have any focus policy and it will delegate focus to the window via a call to QWindow::requestActivate(). However, returning to the normal focus chain from the QWindow instance will be up to the QWindow instance implementation itself. Also, whether QWindow::requestActivate() actually gives the window focus, is platform dependent. Since 6.8, if embedding a Qt Quick based window, tab presses will transition in and out of the embedded QML window, allowing focus to move to the next or previous focusable object in the window container chain. \li Using many window container instances in a QWidget-based application can greatly hurt the overall performance of the application. \li Since 6.7, if \a window belongs to a widget (that is, \a window was received from calling \l windowHandle()), no container will be created. Instead, this function will return the widget itself, after being reparented to \l parent. Since no container will be created, \a flags will be ignored. In other words, if \a window belongs to a widget, consider just reparenting that widget to \a parent instead of using this function. \endlist */ QWidget *QWidget::createWindowContainer(QWindow *window, QWidget *parent,Qt::WindowFlags flags){// Embedding a QWidget in a window container doesn't make sense,// and has various issues in practice, so just return the widget// itself.if(auto*widgetWindow = qobject_cast<QWidgetWindow *>(window)) { QWidget *widget = widgetWindow->widget();if(flags !=Qt::WindowFlags()) {qWarning() << window <<"refers to a widget:"<< widget <<"WindowFlags"<< flags <<"will be ignored.";} widget->setParent(parent);return widget;}return newQWindowContainer(window, parent, flags);}/*! \internal */QWindowContainer::QWindowContainer(QWindow *embeddedWindow, QWidget *parent,Qt::WindowFlags flags):QWidget(*new QWindowContainerPrivate, parent, flags){Q_D(QWindowContainer);if(Q_UNLIKELY(!embeddedWindow)) {qWarning("QWindowContainer: embedded window cannot be null");return;} d->window = embeddedWindow; d->window->installEventFilter(this); QString windowName = d->window->objectName();if(windowName.isEmpty()) windowName =QString::fromUtf8(d->window->metaObject()->className()); d->fakeParent.setObjectName(windowName +"ContainerFakeParent"_L1); d->window->setParent(&d->fakeParent); d->window->parent()->installEventFilter(this); d->window->setFlag(Qt::SubWindow);setAcceptDrops(true);connect(containedWindow(), &QWindow::minimumHeightChanged,this, &QWindowContainer::updateGeometry);connect(containedWindow(), &QWindow::minimumWidthChanged,this, &QWindowContainer::updateGeometry);} QWindow *QWindowContainer::containedWindow()const{Q_D(const QWindowContainer);return d->window;}/*! \internal */QWindowContainer::~QWindowContainer(){Q_D(QWindowContainer);// Call destroy() explicitly first. The dtor would do this too, but// QEvent::PlatformSurface delivery relies on virtuals. Getting// SurfaceAboutToBeDestroyed can be essential for OpenGL, Vulkan, etc.// QWindow subclasses in particular. Keep these working.if(d->window) { d->window->removeEventFilter(this); d->window->destroy();}delete d->window;}/*! \internal */boolQWindowContainer::eventFilter(QObject *o, QEvent *e){Q_D(QWindowContainer);if(!d->window)return false;if(e->type() ==QEvent::ChildRemoved) { QChildEvent *ce =static_cast<QChildEvent *>(e);if(ce->child() == d->window) { o->removeEventFilter(this); d->window->removeEventFilter(this); d->window =nullptr;}}else if(e->type() ==QEvent::FocusIn) {if(o == d->window)setFocus(Qt::ActiveWindowFocusReason);}return false;}/*! \internal */boolQWindowContainer::event(QEvent *e){Q_D(QWindowContainer);if(!d->window)returnQWidget::event(e);QEvent::Type type = e->type();switch(type) {// The only thing we are interested in is making sure our sizes stay// in sync, so do a catch-all case.caseQEvent::Resize: d->updateGeometry();break;caseQEvent::Move: d->updateGeometry();break;caseQEvent::PolishRequest: d->updateGeometry();break;caseQEvent::Show: d->updateUsesNativeWidgets();if(d->isStillAnOrphan()) { d->window->parent()->removeEventFilter(this); d->window->setParent(d->usesNativeWidgets ?windowHandle():window()->windowHandle()); d->fakeParent.destroy();if(d->window->parent()) d->window->parent()->installEventFilter(this);}if(d->window->parent()) { d->markParentChain(); d->window->show();}break;caseQEvent::Hide:if(d->window->parent()) d->window->hide();break;caseQEvent::FocusIn:if(d->window->parent()) {if(QGuiApplication::focusWindow() != d->window) { QFocusEvent *event =static_cast<QFocusEvent *>(e);constauto reason = event->reason();QWindowPrivate::FocusTarget target =QWindowPrivate::FocusTarget::Current;if(reason ==Qt::TabFocusReason) target =QWindowPrivate::FocusTarget::First;else if(reason ==Qt::BacktabFocusReason) target =QWindowPrivate::FocusTarget::Last;qt_window_private(d->window)->setFocusToTarget(target, reason); d->window->requestActivate();}}break;#if QT_CONFIG(draganddrop)caseQEvent::Drop:caseQEvent::DragMove:caseQEvent::DragLeave:QCoreApplication::sendEvent(d->window, e);return e->isAccepted();caseQEvent::DragEnter:// Don't reject drag events for the entire widget when one// item rejects the drag enterQCoreApplication::sendEvent(d->window, e); e->accept();return true;#endifcaseQEvent::Paint:{static bool needsPunch = !QGuiApplicationPrivate::platformIntegration()->hasCapability(QPlatformIntegration::TopStackedNativeChildWindows);if(needsPunch) { QPainter p(this); p.setCompositionMode(QPainter::CompositionMode_Source); p.fillRect(rect(),Qt::transparent);}break;}default:break;}returnQWidget::event(e);} QSize QWindowContainer::minimumSizeHint()const{returncontainedWindow() ?containedWindow()->minimumSize() :QSize(0,0);}typedefvoid(*qwindowcontainer_traverse_callback)(QWidget *parent);static voidqwindowcontainer_traverse(QWidget *parent, qwindowcontainer_traverse_callback callback){const QObjectList &children = parent->children();for(int i=0; i<children.size(); ++i) { QWidget *w = qobject_cast<QWidget *>(children.at(i));if(w) { QWidgetPrivate *wd =static_cast<QWidgetPrivate *>(QWidgetPrivate::get(w));if(wd->extra && wd->extra->hasWindowContainer)callback(w);}}}voidQWindowContainer::toplevelAboutToBeDestroyed(QWidget *parent){if(QWindowContainerPrivate *d =QWindowContainerPrivate::get(parent)) {if(d->window->parent()) d->window->parent()->removeEventFilter(parent); d->window->setParent(&d->fakeParent); d->window->parent()->installEventFilter(parent);}qwindowcontainer_traverse(parent, toplevelAboutToBeDestroyed);}voidQWindowContainer::parentWasChanged(QWidget *parent){if(QWindowContainerPrivate *d =QWindowContainerPrivate::get(parent)) {if(d->window->parent()) { d->updateUsesNativeWidgets(); d->markParentChain(); QWidget *toplevel = d->usesNativeWidgets ? parent : parent->window();if(!toplevel->windowHandle()) { QWidgetPrivate *tld =static_cast<QWidgetPrivate *>(QWidgetPrivate::get(toplevel)); tld->createTLExtra(); tld->createTLSysExtra();Q_ASSERT(toplevel->windowHandle());} d->window->parent()->removeEventFilter(parent); d->window->setParent(toplevel->windowHandle()); toplevel->windowHandle()->installEventFilter(parent); d->fakeParent.destroy(); d->updateGeometry();}}qwindowcontainer_traverse(parent, parentWasChanged);}voidQWindowContainer::parentWasMoved(QWidget *parent){if(QWindowContainerPrivate *d =QWindowContainerPrivate::get(parent)) {if(!d->window)return;else if(d->window->parent()) d->updateGeometry();}qwindowcontainer_traverse(parent, parentWasMoved);}voidQWindowContainer::parentWasRaised(QWidget *parent){if(QWindowContainerPrivate *d =QWindowContainerPrivate::get(parent)) {if(!d->window)return;else if(d->window->parent()) d->window->raise();}qwindowcontainer_traverse(parent, parentWasRaised);}voidQWindowContainer::parentWasLowered(QWidget *parent){if(QWindowContainerPrivate *d =QWindowContainerPrivate::get(parent)) {if(!d->window)return;else if(d->window->parent()) d->window->lower();}qwindowcontainer_traverse(parent, parentWasLowered);} QT_END_NAMESPACE #include"moc_qwindowcontainer_p.cpp"