Unregister aspects when shutting down

This allows the aspect manager to call QAbstractAspect::onUnregistered()
in a symmetric way to onRegistered() before we exit the aspect manager's
main loop.

In particular, this allows the render aspect a chance to cleanly
shutdown the renderer submission thread.

Task-number: QTBUG-51035
Change-Id: I38a2f3d4fa016f451e53f0ceac02c387911aa6c4
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/src/core/aspects/qaspectmanager.cpp b/src/core/aspects/qaspectmanager.cpp
index 9df1112b0..d565848a8 100644
--- a/src/core/aspects/qaspectmanager.cpp
+++ b/src/core/aspects/qaspectmanager.cpp
@@ -196,6 +196,26 @@ void QAspectManager::registerAspect(QAbstractAspect *aspect)
     qCDebug(Aspects) << "Completed registering aspect";
 }
 
+/*!
+ * \internal
+ *
+ * Calls QAbstractAspect::onUnregistered(), unregisters the aspect from the
+ * change arbiter and unsets the arbiter, job manager and aspect manager.
+ * Operations are performed in the reverse order to registerAspect.
+ */
+void QAspectManager::unregisterAspect(Qt3DCore::QAbstractAspect *aspect)
+{
+    qCDebug(Aspects) << "Unregistering aspect";
+    Q_ASSERT(aspect);
+    aspect->onUnregistered();
+    m_changeArbiter->unregisterSceneObserver(aspect->d_func());
+    QAbstractAspectPrivate::get(aspect)->m_arbiter = nullptr;
+    QAbstractAspectPrivate::get(aspect)->m_jobManager = nullptr;
+    QAbstractAspectPrivate::get(aspect)->m_aspectManager = nullptr;
+    m_aspects.removeOne(aspect);
+    qCDebug(Aspects) << "Completed unregistering aspect";
+}
+
 void QAspectManager::exec()
 {
     // Gentlemen, start your engines