3 files changed, 49 insertions, 5 deletions

diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index b1d80d7b8f..b99fca6620 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -276,6 +276,8 @@ QWidgetPrivate::QWidgetPrivate(int version)
       , renderToTextureReallyDirty(1)
       , renderToTextureComposeActive(0)
 #endif
+      , childrenHiddenByWState(0)
+      , childrenShownByExpose(0)
 #if defined(Q_OS_WIN)
       , noPaintOnScreen(0)
 #endif
@@ -9005,13 +9007,23 @@ bool QWidget::event(QEvent *event)
     case QEvent::WindowStateChange: {
         const bool wasMinimized = static_cast<const QWindowStateChangeEvent *>(event)->oldState() & Qt::WindowMinimized;
         if (wasMinimized != isMinimized()) {
+            QWidget *widget = const_cast<QWidget *>(this);
             if (wasMinimized) {
-                QShowEvent showEvent;
-                QCoreApplication::sendEvent(const_cast<QWidget *>(this), &showEvent);
+                // Always send the spontaneous events here, otherwise it can break the application!
+                if (!d->childrenShownByExpose) {
+                    // Show widgets only when they are not yet shown by the expose event
+                    d->showChildren(true);
+                    QShowEvent showEvent;
+                    QCoreApplication::sendSpontaneousEvent(widget, &showEvent);
+                }
+                d->childrenHiddenByWState = false; // Set it always to "false" when window is restored
             } else {
                 QHideEvent hideEvent;
-                QCoreApplication::sendEvent(const_cast<QWidget *>(this), &hideEvent);
+                QCoreApplication::sendSpontaneousEvent(widget, &hideEvent);
+                d->hideChildren(true);
+                d->childrenHiddenByWState = true;
             }
+            d->childrenShownByExpose = false; // Set it always to "false" when window state changes
         }
         changeEvent(event);
     }
diff --git a/src/widgets/kernel/qwidget_p.h b/src/widgets/kernel/qwidget_p.h
index b130c5421a..5f07a8802a 100644
--- a/src/widgets/kernel/qwidget_p.h
+++ b/src/widgets/kernel/qwidget_p.h
@@ -746,6 +746,8 @@ public:
     uint renderToTextureReallyDirty : 1;
     uint renderToTextureComposeActive : 1;
 #endif
+    uint childrenHiddenByWState : 1;
+    uint childrenShownByExpose : 1;
 
     // *************************** Platform specific ************************************
 #if defined(Q_OS_WIN)
diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index 872572a7e2..aa7bcc2ef8 100644
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -871,10 +871,40 @@ void QWidgetWindow::handleDropEvent(QDropEvent *event)
 
 void QWidgetWindow::handleExposeEvent(QExposeEvent *event)
 {
-    if (isExposed()) {
+    QWidgetPrivate *wPriv = m_widget->d_func();
+    const bool exposed = isExposed();
+
+    if (wPriv->childrenHiddenByWState) {
+        // If widgets has been previously hidden by window state change event
+        // and they aren't yet shown...
+        if (exposed) {
+            // If the window becomes exposed...
+            if (!wPriv->childrenShownByExpose) {
+                // ... and they haven't been shown by this function yet - show it.
+                wPriv->showChildren(true);
+                QShowEvent showEvent;
+                QCoreApplication::sendSpontaneousEvent(m_widget, &showEvent);
+                wPriv->childrenShownByExpose = true;
+            }
+        } else {
+            // If the window becomes not exposed...
+            if (wPriv->childrenShownByExpose) {
+                // ... and child widgets was previously shown by the expose event - hide widgets again.
+                // This is a workaround, because sometimes when window is minimized programatically,
+                // the QPA can notify that the window is exposed after changing window state to minimized
+                // and then, the QPA can send next expose event with null exposed region (not exposed).
+                wPriv->hideChildren(true);
+                QHideEvent hideEvent;
+                QCoreApplication::sendSpontaneousEvent(m_widget, &hideEvent);
+                wPriv->childrenShownByExpose = false;
+            }
+        }
+    }
+
+    if (exposed) {
         m_widget->setAttribute(Qt::WA_Mapped);
         if (!event->region().isNull())
-            m_widget->d_func()->syncBackingStore(event->region());
+            wPriv->syncBackingStore(event->region());
     } else {
         m_widget->setAttribute(Qt::WA_Mapped, false);
     }