1 files changed, 154 insertions, 97 deletions

diff --git a/src/widgets/widgets/qcombobox.cpp b/src/widgets/widgets/qcombobox.cpp
index 9a0e969e1c..b249608ccc 100644
--- a/src/widgets/widgets/qcombobox.cpp
+++ b/src/widgets/widgets/qcombobox.cpp
@@ -91,30 +91,11 @@ QT_BEGIN_NAMESPACE
 
 QComboBoxPrivate::QComboBoxPrivate()
     : QWidgetPrivate(),
-      model(0),
-      lineEdit(0),
-      container(0),
-      insertPolicy(QComboBox::InsertAtBottom),
-      sizeAdjustPolicy(QComboBox::AdjustToContentsOnFirstShow),
-      minimumContentsLength(0),
       shownOnce(false),
       autoCompletion(true),
       duplicatesEnabled(false),
       frame(true),
-      maxVisibleItems(10),
-      maxCount(INT_MAX),
-      modelColumn(0),
-      inserting(false),
-      arrowState(QStyle::State_None),
-      hoverControl(QStyle::SC_None),
-      autoCompletionCaseSensitivity(Qt::CaseInsensitive),
-      indexBeforeChange(-1)
-#ifdef Q_OS_MAC
-      , m_platformMenu(0)
-#endif
-#if QT_CONFIG(completer)
-      , completer(0)
-#endif
+      inserting(false)
 {
 }
 
@@ -148,18 +129,26 @@ QStyleOptionMenuItem QComboMenuDelegate::getStyleOption(const QStyleOptionViewIt
     if (option.state & QStyle::State_Selected)
         menuOption.state |= QStyle::State_Selected;
     menuOption.checkType = QStyleOptionMenuItem::NonExclusive;
-    menuOption.checked = mCombo->currentIndex() == index.row();
+    // a valid checkstate means that the model has checkable items
+    const QVariant checkState = index.data(Qt::CheckStateRole);
+    if (!checkState.isValid()) {
+        menuOption.checked = mCombo->currentIndex() == index.row();
+    } else {
+        menuOption.checked = qvariant_cast<int>(checkState) == Qt::Checked;
+        menuOption.state |= qvariant_cast<int>(checkState) == Qt::Checked
+                          ? QStyle::State_On : QStyle::State_Off;
+    }
     if (QComboBoxDelegate::isSeparator(index))
         menuOption.menuItemType = QStyleOptionMenuItem::Separator;
     else
         menuOption.menuItemType = QStyleOptionMenuItem::Normal;
 
     QVariant variant = index.model()->data(index, Qt::DecorationRole);
-    switch (variant.type()) {
-    case QVariant::Icon:
+    switch (variant.userType()) {
+    case QMetaType::QIcon:
         menuOption.icon = qvariant_cast<QIcon>(variant);
         break;
-    case QVariant::Color: {
+    case QMetaType::QColor: {
         static QPixmap pixmap(option.decorationSize);
         pixmap.fill(qvariant_cast<QColor>(variant));
         menuOption.icon = pixmap;
@@ -183,7 +172,7 @@ QStyleOptionMenuItem QComboMenuDelegate::getStyleOption(const QStyleOptionViewIt
     // that order, also override the font for the popup menu.
     QVariant fontRoleData = index.data(Qt::FontRole);
     if (fontRoleData.isValid()) {
-        menuOption.font = fontRoleData.value<QFont>();
+        menuOption.font = qvariant_cast<QFont>(fontRoleData);
     } else if (mCombo->testAttribute(Qt::WA_SetFont)
             || mCombo->testAttribute(Qt::WA_MacSmallSize)
             || mCombo->testAttribute(Qt::WA_MacMiniSize)
@@ -198,6 +187,55 @@ QStyleOptionMenuItem QComboMenuDelegate::getStyleOption(const QStyleOptionViewIt
     return menuOption;
 }
 
+bool QComboMenuDelegate::editorEvent(QEvent *event, QAbstractItemModel *model,
+                                     const QStyleOptionViewItem &option, const QModelIndex &index)
+{
+    Q_ASSERT(event);
+    Q_ASSERT(model);
+
+    // make sure that the item is checkable
+    Qt::ItemFlags flags = model->flags(index);
+    if (!(flags & Qt::ItemIsUserCheckable) || !(option.state & QStyle::State_Enabled)
+        || !(flags & Qt::ItemIsEnabled))
+        return false;
+
+    // make sure that we have a check state
+    const QVariant checkState = index.data(Qt::CheckStateRole);
+    if (!checkState.isValid())
+        return false;
+
+    // make sure that we have the right event type
+    if ((event->type() == QEvent::MouseButtonRelease)
+        || (event->type() == QEvent::MouseButtonDblClick)
+        || (event->type() == QEvent::MouseButtonPress)) {
+        QMouseEvent *me = static_cast<QMouseEvent*>(event);
+        if (me->button() != Qt::LeftButton)
+            return false;
+
+        if ((event->type() == QEvent::MouseButtonPress)
+            || (event->type() == QEvent::MouseButtonDblClick)) {
+            pressedIndex = index.row();
+            return false;
+        }
+
+        if (index.row() != pressedIndex)
+            return false;
+        pressedIndex = -1;
+
+    } else if (event->type() == QEvent::KeyPress) {
+        if (static_cast<QKeyEvent*>(event)->key() != Qt::Key_Space
+         && static_cast<QKeyEvent*>(event)->key() != Qt::Key_Select)
+            return false;
+    } else {
+        return false;
+    }
+
+    // we don't support user-tristate items in QComboBox (not implemented in any style)
+    Qt::CheckState newState = (static_cast<Qt::CheckState>(checkState.toInt()) == Qt::Checked)
+                            ? Qt::Unchecked : Qt::Checked;
+    return model->setData(index, newState, Qt::CheckStateRole);
+}
+
 #if QT_CONFIG(completer)
 void QComboBoxPrivate::_q_completerActivated(const QModelIndex &index)
 {
@@ -255,8 +293,7 @@ void QComboBoxPrivate::_q_modelReset()
         lineEdit->setText(QString());
         updateLineEditGeometry();
     }
-    if (currentIndex.row() != indexBeforeChange)
-        _q_emitCurrentIndexChanged(currentIndex);
+    trySetValidIndex();
     modelChanged();
     q->update();
 }
@@ -266,6 +303,25 @@ void QComboBoxPrivate::_q_modelDestroyed()
     model = QAbstractItemModelPrivate::staticEmptyModel();
 }
 
+void QComboBoxPrivate::trySetValidIndex()
+{
+    Q_Q(QComboBox);
+    bool currentReset = false;
+
+    const int rowCount = q->count();
+    for (int pos = 0; pos < rowCount; ++pos) {
+        const QModelIndex idx(model->index(pos, modelColumn, root));
+        if (idx.flags() & Qt::ItemIsEnabled) {
+            setCurrentIndex(idx);
+            currentReset = true;
+            break;
+        }
+    }
+
+    if (!currentReset)
+        setCurrentIndex(QModelIndex());
+}
+
 QRect QComboBoxPrivate::popupGeometry(int screen) const
 {
     return QStylePrivate::useFullScreenForPopup()
@@ -368,6 +424,8 @@ QSize QComboBoxPrivate::recomputeSizeHint(QSize &sh) const
         }
         if (minimumContentsLength > 0)
             sh.setWidth(qMax(sh.width(), minimumContentsLength * fm.horizontalAdvance(QLatin1Char('X')) + (hasIcon ? iconSize.width() + 4 : 0)));
+        if (!placeholderText.isEmpty())
+            sh.setWidth(qMax(sh.width(), fm.boundingRect(placeholderText).width()));
 
 
         // height
@@ -445,12 +503,8 @@ void QComboBoxPrivateContainer::paintEvent(QPaintEvent *e)
     QFrame::paintEvent(e);
 }
 
-void QComboBoxPrivateContainer::leaveEvent(QEvent *)
-{
-}
-
 QComboBoxPrivateContainer::QComboBoxPrivateContainer(QAbstractItemView *itemView, QComboBox *parent)
-    : QFrame(parent, Qt::Popup), combo(parent), view(0), top(0), bottom(0), maybeIgnoreMouseButtonRelease(false)
+    : QFrame(parent, Qt::Popup), combo(parent)
 {
     // we need the combobox and itemview
     Q_ASSERT(parent);
@@ -555,7 +609,7 @@ void QComboBoxPrivateContainer::updateScrollers()
 */
 void QComboBoxPrivateContainer::viewDestroyed()
 {
-    view = 0;
+    view = nullptr;
     setItemView(new QComboBoxListView());
 }
 
@@ -589,7 +643,7 @@ void QComboBoxPrivateContainer::setItemView(QAbstractItemView *itemView)
 
         if (isAncestorOf(view))
             delete view;
-        view = 0;
+        view = nullptr;
     }
 
     // setup the item view
@@ -851,20 +905,9 @@ QStyleOptionComboBox QComboBoxPrivateContainer::comboStyleOption() const
     The item's \a index is passed. Note that this signal is sent even
     when the choice is not changed. If you need to know when the
     choice actually changes, use signal currentIndexChanged().
-
 */
 
 /*!
-    \fn void QComboBox::activated(const QString &text)
-
-    This signal is sent when the user chooses an item in the combobox.
-    The item's \a text is passed. Note that this signal is sent even
-    when the choice is not changed. If you need to know when the
-    choice actually changes, use signal currentIndexChanged().
-
-    \obsolete Use QComboBox::textActivated() instead
-*/
-/*!
     \fn void QComboBox::textActivated(const QString &text)
     \since 5.14
 
@@ -882,14 +925,6 @@ QStyleOptionComboBox QComboBoxPrivateContainer::comboStyleOption() const
 */
 
 /*!
-    \fn void QComboBox::highlighted(const QString &text)
-
-    This signal is sent when an item in the combobox popup list is
-    highlighted by the user. The item's \a text is passed.
-
-    \obsolete Use textHighlighted() instead
-*/
-/*!
     \fn void QComboBox::textHighlighted(const QString &text)
     \since 5.14
 
@@ -929,7 +964,7 @@ QStyleOptionComboBox QComboBoxPrivateContainer::comboStyleOption() const
     model QStandardItemModel.
 */
 QComboBox::QComboBox(QWidget *parent)
-    : QWidget(*new QComboBoxPrivate(), parent, 0)
+    : QWidget(*new QComboBoxPrivate(), parent, { })
 {
     Q_D(QComboBox);
     d->init();
@@ -939,7 +974,7 @@ QComboBox::QComboBox(QWidget *parent)
   \internal
 */
 QComboBox::QComboBox(QComboBoxPrivate &dd, QWidget *parent)
-    : QWidget(dd, parent, 0)
+    : QWidget(dd, parent, { })
 {
     Q_D(QComboBox);
     d->init();
@@ -1110,8 +1145,9 @@ void QComboBoxPrivate::_q_rowsInserted(const QModelIndex &parent, int start, int
         q->updateGeometry();
     }
 
-    // set current index if combo was previously empty
-    if (start == 0 && (end - start + 1) == q->count() && !currentIndex.isValid()) {
+    // set current index if combo was previously empty and there is no placeholderText
+    if (start == 0 && (end - start + 1) == q->count() && !currentIndex.isValid() &&
+        placeholderText.isEmpty()) {
         q->setCurrentIndex(0);
         // need to emit changed if model updated index "silently"
     } else if (currentIndex.row() != indexBeforeChange) {
@@ -1214,10 +1250,9 @@ void QComboBox::initStyleOption(QStyleOptionComboBox *option) const
     } else {
         option->activeSubControls = d->hoverControl;
     }
-    if (d->currentIndex.isValid()) {
-        option->currentText = currentText();
+    option->currentText = currentText();
+    if (d->currentIndex.isValid())
         option->currentIcon = d->itemIcon(d->currentIndex);
-    }
     option->iconSize = iconSize();
     if (d->container && d->container->isVisible())
         option->state |= QStyle::State_On;
@@ -1370,12 +1405,6 @@ void QComboBoxPrivate::emitActivated(const QModelIndex &index)
     QString text(itemText(index));
     emit q->activated(index.row());
     emit q->textActivated(text);
-#if QT_DEPRECATED_SINCE(5, 15)
-QT_WARNING_PUSH
-QT_WARNING_DISABLE_DEPRECATED
-    emit q->activated(text);
-QT_WARNING_POP
-#endif
 }
 
 void QComboBoxPrivate::_q_emitHighlighted(const QModelIndex &index)
@@ -1386,12 +1415,6 @@ void QComboBoxPrivate::_q_emitHighlighted(const QModelIndex &index)
     QString text(itemText(index));
     emit q->highlighted(index.row());
     emit q->textHighlighted(text);
-#if QT_DEPRECATED_SINCE(5, 15)
-QT_WARNING_PUSH
-QT_WARNING_DISABLE_DEPRECATED
-    emit q->highlighted(text);
-QT_WARNING_POP
-#endif
 }
 
 void QComboBoxPrivate::_q_emitCurrentIndexChanged(const QModelIndex &index)
@@ -1566,7 +1589,7 @@ void QComboBox::setAutoCompletion(bool enable)
         d->lineEdit->setCompleter(d->completer);
         d->completer->setWidget(this);
     } else {
-        d->lineEdit->setCompleter(0);
+        d->lineEdit->setCompleter(nullptr);
     }
 }
 
@@ -1755,7 +1778,7 @@ QSize QComboBox::iconSize() const
     if (d->iconSize.isValid())
         return d->iconSize;
 
-    int iconWidth = style()->pixelMetric(QStyle::PM_SmallIconSize, 0, this);
+    int iconWidth = style()->pixelMetric(QStyle::PM_SmallIconSize, nullptr, this);
     return QSize(iconWidth, iconWidth);
 }
 
@@ -1772,6 +1795,45 @@ void QComboBox::setIconSize(const QSize &size)
 }
 
 /*!
+    \property QComboBox::placeholderText
+    \brief Sets a \a placeholderText text shown when no valid index is set
+
+    The \a placeholderText will be shown when an invalid index is set. The
+    text is not accessible in the dropdown list. When this function is called
+    before items are added the placeholder text will be shown, otherwise you
+    have to call setCurrentIndex(-1) programmatically if you want to show the
+    placeholder text.
+    Set an empty placeholder text to reset the setting.
+
+    When the QComboBox is editable, use QLineEdit::setPlaceholderText()
+    instead.
+
+    \since 5.15
+*/
+void QComboBox::setPlaceholderText(const QString &placeholderText)
+{
+    Q_D(QComboBox);
+    if (placeholderText == d->placeholderText)
+        return;
+
+    d->placeholderText = placeholderText;
+    if (currentIndex() == -1) {
+      if (d->placeholderText.isEmpty() && currentIndex() == -1)
+        setCurrentIndex(0);
+      else
+        update();
+    } else {
+      updateGeometry();
+    }
+}
+
+QString QComboBox::placeholderText() const
+{
+    Q_D(const QComboBox);
+    return d->placeholderText;
+}
+
+/*!
     \property QComboBox::editable
     \brief whether the combo box can be edited by the user
 
@@ -1786,7 +1848,7 @@ void QComboBox::setIconSize(const QSize &size)
 bool QComboBox::isEditable() const
 {
     Q_D(const QComboBox);
-    return d->lineEdit != 0;
+    return d->lineEdit != nullptr;
 }
 
 /*! \internal
@@ -1813,7 +1875,7 @@ void QComboBoxPrivate::updateDelegate(bool force)
 QIcon QComboBoxPrivate::itemIcon(const QModelIndex &index) const
 {
     QVariant decoration = model->data(index, Qt::DecorationRole);
-    if (decoration.type() == QVariant::Pixmap)
+    if (decoration.userType() == QMetaType::QPixmap)
         return QIcon(qvariant_cast<QPixmap>(decoration));
     else
         return qvariant_cast<QIcon>(decoration);
@@ -1842,7 +1904,7 @@ void QComboBox::setEditable(bool editable)
         setAttribute(Qt::WA_InputMethodEnabled, false);
         d->lineEdit->hide();
         d->lineEdit->deleteLater();
-        d->lineEdit = 0;
+        d->lineEdit = nullptr;
     }
 
     d->updateDelegate();
@@ -1891,6 +1953,8 @@ void QComboBox::setLineEdit(QLineEdit *edit)
     d->lineEdit->setFocusProxy(this);
     d->lineEdit->setAttribute(Qt::WA_MacShowFocusRect, false);
 #if QT_DEPRECATED_SINCE(5, 13)
+QT_WARNING_PUSH
+QT_WARNING_DISABLE_DEPRECATED
 #if QT_CONFIG(completer)
     setAutoCompletion(d->autoCompletion);
 
@@ -1907,6 +1971,7 @@ void QComboBox::setLineEdit(QLineEdit *edit)
     }
 #endif
 #endif
+QT_WARNING_POP
 #endif
 
     setAttribute(Qt::WA_InputMethodEnabled);
@@ -1955,7 +2020,7 @@ void QComboBox::setValidator(const QValidator *v)
 const QValidator *QComboBox::validator() const
 {
     Q_D(const QComboBox);
-    return d->lineEdit ? d->lineEdit->validator() : 0;
+    return d->lineEdit ? d->lineEdit->validator() : nullptr;
 }
 #endif // QT_NO_VALIDATOR
 
@@ -1966,7 +2031,7 @@ const QValidator *QComboBox::validator() const
     \since 4.2
 
     Sets the \a completer to use instead of the current completer.
-    If \a completer is 0, auto completion is disabled.
+    If \a completer is \nullptr, auto completion is disabled.
 
     By default, for an editable combo box, a QCompleter that
     performs case insensitive inline completion is automatically created.
@@ -1999,7 +2064,7 @@ void QComboBox::setCompleter(QCompleter *c)
 QCompleter *QComboBox::completer() const
 {
     Q_D(const QComboBox);
-    return d->lineEdit ? d->lineEdit->completer() : 0;
+    return d->lineEdit ? d->lineEdit->completer() : nullptr;
 }
 
 #endif // QT_CONFIG(completer)
@@ -2018,6 +2083,9 @@ QAbstractItemDelegate *QComboBox::itemDelegate() const
     Sets the item \a delegate for the popup list view.
     The combobox takes ownership of the delegate.
 
+    Any existing delegate will be removed, but not deleted. QComboBox
+    does not take ownership of \a delegate.
+
     \warning You should not share the same instance of a delegate between comboboxes,
     widget mappers or views. Doing so can cause incorrect or unintuitive editing behavior
     since each view connected to a given delegate may receive the
@@ -2032,7 +2100,6 @@ void QComboBox::setItemDelegate(QAbstractItemDelegate *delegate)
         qWarning("QComboBox::setItemDelegate: cannot set a 0 delegate");
         return;
     }
-    delete view()->itemDelegate();
     view()->setItemDelegate(delegate);
 }
 
@@ -2122,20 +2189,7 @@ void QComboBox::setModel(QAbstractItemModel *model)
 
     setRootModelIndex(QModelIndex());
 
-    bool currentReset = false;
-
-    const int rowCount = count();
-    for (int pos=0; pos < rowCount; pos++) {
-        if (d->model->index(pos, d->modelColumn, d->root).flags() & Qt::ItemIsEnabled) {
-            setCurrentIndex(pos);
-            currentReset = true;
-            break;
-        }
-    }
-
-    if (!currentReset)
-        setCurrentIndex(-1);
-
+    d->trySetValidIndex();
     d->modelChanged();
 }
 
@@ -2249,7 +2303,7 @@ QString QComboBox::currentText() const
     else if (d->currentIndex.isValid())
         return d->itemText(d->currentIndex);
     else
-        return QString();
+        return d->placeholderText;
 }
 
 /*!
@@ -2886,7 +2940,7 @@ void QComboBox::hidePopup()
         QSignalBlocker containerBlocker(d->container);
         // Flash selected/triggered item (if any).
         if (style()->styleHint(QStyle::SH_Menu_FlashTriggeredItem)) {
-            QItemSelectionModel *selectionModel = view() ? view()->selectionModel() : 0;
+            QItemSelectionModel *selectionModel = view() ? view()->selectionModel() : nullptr;
             if (selectionModel && selectionModel->hasSelection()) {
                 QEventLoop eventLoop;
                 const QItemSelection selection = selectionModel->selection();
@@ -3079,6 +3133,9 @@ void QComboBox::paintEvent(QPaintEvent *)
     initStyleOption(&opt);
     painter.drawComplexControl(QStyle::CC_ComboBox, opt);
 
+    if (currentIndex() < 0)
+        opt.palette.setBrush(QPalette::ButtonText, opt.palette.brush(QPalette::ButtonText).color().lighter());
+
     // draw the icon and text
     painter.drawControl(QStyle::CE_ComboBoxLabel, opt);
 }