3 files changed, 56 insertions, 8 deletions

diff --git a/src/widgets/widgets/qcombobox.cpp b/src/widgets/widgets/qcombobox.cpp
index bdd06da7fc..90310308c3 100644
--- a/src/widgets/widgets/qcombobox.cpp
+++ b/src/widgets/widgets/qcombobox.cpp
@@ -407,7 +407,7 @@ void QComboBoxPrivateContainer::leaveEvent(QEvent *)
 }
 
 QComboBoxPrivateContainer::QComboBoxPrivateContainer(QAbstractItemView *itemView, QComboBox *parent)
-    : QFrame(parent, Qt::Popup), combo(parent), view(0), top(0), bottom(0)
+    : QFrame(parent, Qt::Popup), combo(parent), view(0), top(0), bottom(0), maybeIgnoreMouseButtonRelease(false)
 {
     // we need the combobox and itemview
     Q_ASSERT(parent);
@@ -667,10 +667,15 @@ bool QComboBoxPrivateContainer::eventFilter(QObject *o, QEvent *e)
             }
         }
         break;
+    case QEvent::MouseButtonPress:
+        maybeIgnoreMouseButtonRelease = false;
+        break;
     case QEvent::MouseButtonRelease: {
+        bool ignoreEvent = maybeIgnoreMouseButtonRelease && popupTimer.elapsed() < QApplication::doubleClickInterval();
+
         QMouseEvent *m = static_cast<QMouseEvent *>(e);
         if (isVisible() && view->rect().contains(m->pos()) && view->currentIndex().isValid()
-            && !blockMouseReleaseTimer.isActive()
+            && !blockMouseReleaseTimer.isActive() && !ignoreEvent
             && (view->currentIndex().flags() & Qt::ItemIsEnabled)
             && (view->currentIndex().flags() & Qt::ItemIsSelectable)) {
             combo->hidePopup();
@@ -2562,6 +2567,7 @@ void QComboBox::showPopup()
     container->setUpdatesEnabled(false);
 #endif
 
+    bool startTimer = !container->isVisible();
     container->raise();
     container->show();
     container->updateScrollers();
@@ -2581,6 +2587,10 @@ void QComboBox::showPopup()
     if (QApplication::keypadNavigationEnabled())
         view()->setEditFocus(true);
 #endif
+    if (startTimer) {
+        container->popupTimer.start();
+        container->maybeIgnoreMouseButtonRelease = true;
+    }
 }
 
 /*!
@@ -2876,6 +2886,11 @@ void QComboBox::mousePressEvent(QMouseEvent *e)
         }
 #endif
         showPopup();
+        // The code below ensures that regular mousepress and pick item still works
+        // If it was not called the viewContainer would ignore event since it didn't have
+        // a mousePressEvent first.
+        if (d->viewContainer())
+            d->viewContainer()->maybeIgnoreMouseButtonRelease = false;
     } else {
 #ifdef QT_KEYPAD_NAVIGATION
         if (QApplication::keypadNavigationEnabled() && sc == QStyle::SC_ComboBoxEditField && d->lineEdit) {
diff --git a/src/widgets/widgets/qcombobox_p.h b/src/widgets/widgets/qcombobox_p.h
index 07ba9b0925..1ad2aa455a 100644
--- a/src/widgets/widgets/qcombobox_p.h
+++ b/src/widgets/widgets/qcombobox_p.h
@@ -254,6 +254,10 @@ private:
     QAbstractItemView *view;
     QComboBoxPrivateScroller *top;
     QComboBoxPrivateScroller *bottom;
+    bool maybeIgnoreMouseButtonRelease;
+    QElapsedTimer popupTimer;
+
+    friend class QComboBox;
 };
 
 class QComboMenuDelegate : public QAbstractItemDelegate
diff --git a/tests/manual/widgets/itemviews/delegate/example.cpp b/tests/manual/widgets/itemviews/delegate/example.cpp
index c65f49f266..dcebf437b1 100644
--- a/tests/manual/widgets/itemviews/delegate/example.cpp
+++ b/tests/manual/widgets/itemviews/delegate/example.cpp
@@ -45,6 +45,7 @@
 #include <QStandardItemModel>
 #include <QItemDelegate>
 #include <QDebug>
+#include <QComboBox>
 
 class ExampleEditor : public QLineEdit
 {
@@ -56,13 +57,26 @@ public:
 class ExampleDelegate : public QItemDelegate
 {
 public:
-    ExampleDelegate():QItemDelegate() { m_editor = new ExampleEditor(0); }
+    ExampleDelegate() : QItemDelegate()
+    {
+        m_editor = new ExampleEditor(0);
+        m_combobox = new QComboBox(0);
+        m_combobox->addItem(QString::fromUtf8("item1"));
+        m_combobox->addItem(QString::fromUtf8("item2"));
+    }
 protected:
-    QWidget* createEditor(QWidget *p, const QStyleOptionViewItem &o, const QModelIndex &) const
+    QWidget* createEditor(QWidget *p, const QStyleOptionViewItem &o, const QModelIndex &i) const
     {
-        m_editor->setParent(p);
-        m_editor->setGeometry(o.rect);
-        return m_editor;
+        // doubleclick rownumber 3 (last row) to see the difference.
+        if (i.row() == 3) {
+            m_combobox->setParent(p);
+            m_combobox->setGeometry(o.rect);
+            return m_combobox;
+        } else {
+            m_editor->setParent(p);
+            m_editor->setGeometry(o.rect);
+            return m_editor;
+        }
     }
     void destroyEditor(QWidget *editor, const QModelIndex &) const
     {
@@ -71,10 +85,25 @@ protected:
     }
 
     // Avoid setting data - and therefore show that the editor keeps its state.
-    void setEditorData(QWidget*, const QModelIndex &) const { }
+    void setEditorData(QWidget* w, const QModelIndex &) const
+    {
+        QComboBox *combobox = qobject_cast<QComboBox*>(w);
+        if (combobox) {
+            qDebug() << "Try to show popup at once";
+            // Now we could try to make a call to
+            // QCoreApplication::processEvents();
+            // But it does not matter. The fix:
+            // https://codereview.qt-project.org/40608
+            // is blocking QComboBox from reacting to this doubleclick edit event
+            // and we need to do that since the mouseReleaseEvent has not yet happened,
+            // and therefore cannot be processed.
+            combobox->showPopup();
+        }
+    }
 
     ~ExampleDelegate() { delete m_editor; }
     mutable ExampleEditor *m_editor;
+    mutable QComboBox *m_combobox;
 };
 
 int main(int argc, char *argv[])