Menu: Enable mnemonic menu navigation

We also added a new mnemonic specific shortcut context matcher. This
prevents two menu items with the same mnemonic but within different
menus to be reported as ambiguous.

Task-number: QTBUG-33030
ChangeLog: Added mnemonic navigation for menus
Change-Id: I192c9aacba4d15851fe65bf9201251962fe976d5
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>

12 files changed, 176 insertions, 29 deletions

diff --git a/examples/quick/controls/gallery/main.qml b/examples/quick/controls/gallery/main.qml
index ec00627b..2896c356 100644
--- a/examples/quick/controls/gallery/main.qml
+++ b/examples/quick/controls/gallery/main.qml
@@ -111,20 +111,20 @@ ApplicationWindow {
 
         Action {
             id: a1
-            text: "Align Left"
+            text: "Align &Left"
             checkable: true
             Component.onCompleted: checked = true
         }
 
         Action {
             id: a2
-            text: "Center"
+            text: "&Center"
             checkable: true
         }
 
         Action {
             id: a3
-            text: "Align Right"
+            text: "Align &Right"
             checkable: true
         }
     }
@@ -138,18 +138,18 @@ ApplicationWindow {
         MenuItem { action: pasteAction }
         MenuSeparator {}
         Menu {
-            title: "Text Format"
+            title: "Text &Format"
             MenuItem { action: a1 }
             MenuItem { action: a2 }
             MenuItem { action: a3 }
             MenuSeparator { }
-            MenuItem { text: "Allow Hyphenation"; checkable: true }
+            MenuItem { text: "Allow &Hyphenation"; checkable: true }
         }
         Menu {
-            title: "Font Style"
-            MenuItem { text: "Bold"; checkable: true }
-            MenuItem { text: "Italic"; checkable: true }
-            MenuItem { text: "Underline"; checkable: true }
+            title: "Font &Style"
+            MenuItem { text: "&Bold"; checkable: true }
+            MenuItem { text: "&Italic"; checkable: true }
+            MenuItem { text: "&Underline"; checkable: true }
         }
     }
 
diff --git a/src/controls/ApplicationWindow.qml b/src/controls/ApplicationWindow.qml
index 364b2b11..8967a8a1 100644
--- a/src/controls/ApplicationWindow.qml
+++ b/src/controls/ApplicationWindow.qml
@@ -133,6 +133,8 @@ Window {
         id: backgroundItem
         anchors.fill: parent
 
+        Keys.forwardTo: [menuBar.__contentItem]
+
         Item {
             id: contentArea
             anchors.top: toolBarArea.bottom
diff --git a/src/controls/Menu.qml b/src/controls/Menu.qml
index 6c9f8fd2..525b0737 100644
--- a/src/controls/Menu.qml
+++ b/src/controls/Menu.qml
@@ -133,7 +133,7 @@ MenuPrivate {
     property Component style: Qt.createComponent(Settings.style + "/MenuStyle.qml", root)
 
     /*! \internal */
-    property var __menuBar: null
+    property var __parentContentItem: __parentMenu.__contentItem
     /*! \internal */
     property int __currentIndex: -1
     /*! \internal */
@@ -144,6 +144,8 @@ MenuPrivate {
         sourceComponent: __menuComponent
         active: !root.__isNative && root.__popupVisible
         focus: true
+        Keys.forwardTo: item ? [item, root.__parentContentItem] : []
+        property bool altPressed: root.__parentContentItem ? root.__parentContentItem.altPressed : false
     }
 
     /*! \internal */
@@ -174,14 +176,30 @@ MenuPrivate {
         }
 
         focus: true
-        Keys.forwardTo: __menuBar ? [__menuBar] : []
+        property var mnemonicsMap: ({})
+
+        Keys.onPressed: {
+            var item = null
+            if (!(event.modifiers & Qt.AltModifier)
+                && (item = mnemonicsMap[event.text.toUpperCase()])) {
+                if (item.isSubmenu) {
+                    root.__currentIndex = item.menuItemIndex
+                    item.showSubMenu(true)
+                    item.menuItem.__currentIndex = 0
+                } else {
+                    triggerAndDismiss(item)
+                }
+                event.accepted = true
+            } else {
+                event.accepted = false
+            }
+        }
+
         Keys.onEscapePressed: root.__dismissMenu()
 
         Keys.onDownPressed: {
-            if (root.__currentIndex < 0) {
-                root.__currentIndex = 0
-                return
-            }
+            if (root.__currentIndex < 0)
+                root.__currentIndex = -1
 
             for (var i = root.__currentIndex + 1;
                  i < root.items.length && !canBeHovered(i); i++)
@@ -204,13 +222,13 @@ MenuPrivate {
         }
 
         Keys.onLeftPressed: {
-            if (root.__parentMenu)
+            if ((event.accepted = root.__parentMenu.hasOwnProperty("title")))
                 __closeMenu()
         }
 
         Keys.onRightPressed: {
             var item = itemsRepeater.itemAt(root.__currentIndex)
-            if (item && item.isSubmenu) {
+            if ((event.accepted = (item && item.isSubmenu))) {
                 item.showSubMenu(true)
                 item.menuItem.__currentIndex = 0
             }
@@ -220,8 +238,9 @@ MenuPrivate {
         Keys.onReturnPressed: menuFrameLoader.triggerAndDismiss()
         Keys.onEnterPressed: menuFrameLoader.triggerAndDismiss()
 
-        function triggerAndDismiss() {
-            var item = itemsRepeater.itemAt(root.__currentIndex)
+        function triggerAndDismiss(item) {
+            if (!item)
+                item = itemsRepeater.itemAt(root.__currentIndex)
             if (item && !item.isSeparator) {
                 root.__dismissMenu()
                 if (!item.isSubmenu)
@@ -261,7 +280,7 @@ MenuPrivate {
                     var itemUnderMouse = column.childAt(pos.x, pos.y)
                     if (itemUnderMouse) {
                         currentItem = itemUnderMouse
-                    } else {
+                    } else if (currentItem) {
                         var itemItem = currentItem.item
                         if (!itemItem.contains(itemItem.mapFromItem(column, pos)))
                             currentItem = null
@@ -294,6 +313,7 @@ MenuPrivate {
                         readonly property bool isSubmenu: !!menuItem && menuItem.type === MenuItemType.Menu
                         property bool selected: !isSeparator && root.__currentIndex === index
                         property string text: isSubmenu ? menuItem.title : !isSeparator ? menuItem.text : ""
+                        property bool showUnderlined: __contentItem.altPressed
 
                         property int menuItemIndex: index
 
@@ -328,7 +348,14 @@ MenuPrivate {
                             }
                         }
 
-                        Component.onCompleted: menuItem.__visualItem = menuItemLoader
+                        Component.onCompleted: {
+                            menuItem.__visualItem = menuItemLoader
+
+                            var title = text
+                            var ampersandPos = title.indexOf("&")
+                            if (ampersandPos !== -1)
+                                menuFrameLoader.mnemonicsMap[title[ampersandPos + 1].toUpperCase()] = menuItemLoader
+                        }
                     }
                 }
 
diff --git a/src/controls/MenuBar.qml b/src/controls/MenuBar.qml
index eabb4d48..a126c7c6 100644
--- a/src/controls/MenuBar.qml
+++ b/src/controls/MenuBar.qml
@@ -82,6 +82,8 @@ MenuBarPrivate {
         sourceComponent: __menuBarComponent
         active: !root.__isNative
         focus: true
+        Keys.forwardTo: [item]
+        property bool altPressed: item ? item.altPressed : false
     }
 
     /*! \internal */
@@ -118,7 +120,51 @@ MenuBarPrivate {
             value: menuMouseArea.z - 1
         }
 
-        focus: openedMenuIndex !== -1
+        focus: true
+
+        property bool altPressed: false
+        property bool altPressedAgain: false
+        property var mnemonicsMap: ({})
+
+        Keys.onPressed: {
+            var action = null
+            if (event.key === Qt.Key_Alt) {
+                if (!altPressed)
+                    altPressed = true
+                else
+                    altPressedAgain = true
+            } else if (altPressed && (action = mnemonicsMap[event.text.toUpperCase()])) {
+                preselectMenuItem = true
+                action.trigger()
+                event.accepted = true
+            }
+        }
+
+        function dismissActiveFocus(event, reason) {
+            if (reason) {
+                altPressedAgain = false
+                altPressed = false
+                openedMenuIndex = -1
+                root.__contentItem.parent.forceActiveFocus()
+            } else {
+                event.accepted = false
+            }
+        }
+
+        Keys.onReleased: dismissActiveFocus(event, altPressedAgain && openedMenuIndex === -1)
+        Keys.onEscapePressed: dismissActiveFocus(event, openedMenuIndex === -1)
+
+        function maybeOpenFirstMenu(event) {
+            if (altPressed && openedMenuIndex === -1) {
+                preselectMenuItem = true
+                openedMenuIndex = 0
+            } else {
+                event.accepted = false
+            }
+        }
+
+        Keys.onUpPressed: maybeOpenFirstMenu(event)
+        Keys.onDownPressed: maybeOpenFirstMenu(event)
 
         Keys.onLeftPressed: {
             if (openedMenuIndex > 0) {
@@ -128,7 +174,7 @@ MenuBarPrivate {
         }
 
         Keys.onRightPressed: {
-            if (openedMenuIndex < root.menus.length - 1) {
+            if (openedMenuIndex !== -1 && openedMenuIndex < root.menus.length - 1) {
                 preselectMenuItem = true
                 openedMenuIndex++
             }
@@ -177,6 +223,7 @@ MenuBarPrivate {
                         property var menuItem: modelData
                         property bool selected: menuMouseArea.hoveredItem === menuItemLoader
                         property bool sunken: menuItem.__popupVisible || menuBarLoader.openedMenuIndex === index
+                        property bool showUnderlined: menuBarLoader.altPressed
 
                         sourceComponent: menuBarLoader.menuItemStyle
                         property int menuItemIndex: index
@@ -203,9 +250,18 @@ MenuBarPrivate {
                             }
                         }
 
+                        Connections {
+                            target: menuItem.__action
+                            onTriggered: menuBarLoader.openedMenuIndex = menuItemIndex
+                        }
+
                         Component.onCompleted: {
                             menuItem.__visualItem = menuItemLoader
-                            menuItem.__menuBar = menuBarLoader
+
+                            var title = menuItem.title
+                            var ampersandPos = title.indexOf("&")
+                            if (ampersandPos !== -1)
+                                menuBarLoader.mnemonicsMap[title[ampersandPos + 1].toUpperCase()] = menuItem.__action
                         }
                     }
                 }
diff --git a/src/controls/qquickaction.cpp b/src/controls/qquickaction.cpp
index e240d111..6a031404 100644
--- a/src/controls/qquickaction.cpp
+++ b/src/controls/qquickaction.cpp
@@ -41,6 +41,7 @@
 
 #include "qquickaction_p.h"
 #include "qquickexclusivegroup_p.h"
+#include "qquickmenuitem_p.h"
 
 #include <QtGui/qguiapplication.h>
 #include <QtQuick/qquickitem.h>
@@ -203,6 +204,8 @@ void QQuickAction::setText(const QString &text)
     emit textChanged();
 }
 
+namespace {
+
 bool qShortcutContextMatcher(QObject *o, Qt::ShortcutContext context)
 {
     switch (context) {
@@ -226,6 +229,38 @@ bool qShortcutContextMatcher(QObject *o, Qt::ShortcutContext context)
     return false;
 }
 
+bool qMnemonicContextMatcher(QObject *o, Qt::ShortcutContext context)
+{
+    switch (context) {
+    case Qt::ApplicationShortcut:
+        return true;
+    case Qt::WindowShortcut: {
+        QObject *w = o;
+        while (w && !w->isWindowType()) {
+            w = w->parent();
+            if (QQuickItem * item = qobject_cast<QQuickItem*>(w))
+                w = item->window();
+            else if (QQuickMenuBase *mb = qobject_cast<QQuickMenuBase *>(w)) {
+                QQuickItem *vi = mb->visualItem();
+                if (vi && vi->isVisible())
+                    w = vi->window();
+                else
+                    break; // Non visible menu objects don't get mnemonic match
+            }
+        }
+        if (w && w == QGuiApplication::focusWindow())
+            return true;
+    }
+    case Qt::WidgetShortcut:
+    case Qt::WidgetWithChildrenShortcut:
+        break;
+    }
+
+    return false;
+}
+
+} // namespace
+
 QString QQuickAction::shortcut() const
 {
     return m_shortcut.toString(QKeySequence::NativeText);
@@ -262,7 +297,7 @@ void QQuickAction::setMnemonicFromText(const QString &text)
 
     if (!m_mnemonic.isEmpty()) {
         Qt::ShortcutContext context = Qt::WindowShortcut;
-        QGuiApplicationPrivate::instance()->shortcutMap.addShortcut(this, m_mnemonic, context, qShortcutContextMatcher);
+        QGuiApplicationPrivate::instance()->shortcutMap.addShortcut(this, m_mnemonic, context, qMnemonicContextMatcher);
     }
 }
 
diff --git a/src/controls/qquickmenu.cpp b/src/controls/qquickmenu.cpp
index 2dbaf952..f65d7044 100644
--- a/src/controls/qquickmenu.cpp
+++ b/src/controls/qquickmenu.cpp
@@ -401,8 +401,10 @@ void QQuickMenu::__popup(qreal x, qreal y, int atItemIndex)
 
 void QQuickMenu::setMenuContentItem(QQuickItem *item)
 {
-    if (m_menuContentItem != item)
+    if (m_menuContentItem != item) {
         m_menuContentItem = item;
+        emit menuContentItemChanged();
+    }
 }
 
 void QQuickMenu::setPopupVisible(bool v)
diff --git a/src/controls/qquickmenu_p.h b/src/controls/qquickmenu_p.h
index 54f7451b..f15e6caa 100644
--- a/src/controls/qquickmenu_p.h
+++ b/src/controls/qquickmenu_p.h
@@ -68,11 +68,12 @@ class QQuickMenu : public QQuickMenuText
 
     Q_PROPERTY(int __selectedIndex READ selectedIndex WRITE setSelectedIndex NOTIFY __selectedIndexChanged)
     Q_PROPERTY(bool __popupVisible READ popupVisible NOTIFY popupVisibleChanged)
-    Q_PROPERTY(QQuickItem *__contentItem READ menuContentItem WRITE setMenuContentItem)
+    Q_PROPERTY(QQuickItem *__contentItem READ menuContentItem WRITE setMenuContentItem NOTIFY menuContentItemChanged)
     Q_PROPERTY(int __minimumWidth READ minimumWidth WRITE setMinimumWidth)
     Q_PROPERTY(QFont __font READ font WRITE setFont)
     Q_PROPERTY(qreal __xOffset READ xOffset WRITE setXOffset)
     Q_PROPERTY(qreal __yOffset READ yOffset WRITE setYOffset)
+    Q_PROPERTY(QQuickAction *__action READ action CONSTANT)
 
 public:
     Q_INVOKABLE void popup();
@@ -98,6 +99,7 @@ Q_SIGNALS:
     void __selectedIndexChanged();
     void __menuClosed();
     void popupVisibleChanged();
+    void menuContentItemChanged();
 
 public:
     QQuickMenu(QObject *parent = 0);
diff --git a/src/controls/qquickmenuitem.cpp b/src/controls/qquickmenuitem.cpp
index 2fda7e00..4d276ac1 100644
--- a/src/controls/qquickmenuitem.cpp
+++ b/src/controls/qquickmenuitem.cpp
@@ -84,6 +84,13 @@ void QQuickMenuBase::setVisible(bool v)
     }
 }
 
+QObject *QQuickMenuBase::parentMenuOrMenuBar() const
+{
+    if (!m_parentMenu)
+        return parent();
+    return m_parentMenu;
+}
+
 QQuickMenu *QQuickMenuBase::parentMenu() const
 {
     return m_parentMenu;
diff --git a/src/controls/qquickmenuitem_p.h b/src/controls/qquickmenuitem_p.h
index 02e7f5e3..791a0edb 100644
--- a/src/controls/qquickmenuitem_p.h
+++ b/src/controls/qquickmenuitem_p.h
@@ -78,7 +78,7 @@ class QQuickMenuBase: public QObject
     Q_PROPERTY(bool visible READ visible WRITE setVisible NOTIFY visibleChanged)
     Q_PROPERTY(QQuickMenuItemType::MenuItemType type READ type CONSTANT)
 
-    Q_PROPERTY(QQuickMenu *__parentMenu READ parentMenu CONSTANT)
+    Q_PROPERTY(QObject *__parentMenu READ parentMenuOrMenuBar CONSTANT)
     Q_PROPERTY(bool __isNative READ isNative CONSTANT)
     Q_PROPERTY(QQuickItem *__visualItem READ visualItem WRITE setVisualItem)
 
@@ -93,6 +93,7 @@ public:
     virtual void setVisible(bool);
 
     QQuickMenu *parentMenu() const;
+    QObject *parentMenuOrMenuBar() const;
     virtual void setParentMenu(QQuickMenu *parentMenu);
 
     QQuickMenuItemContainer *container() const;
diff --git a/src/private/qquickstyleitem.cpp b/src/private/qquickstyleitem.cpp
index b8edbd2d..d0f3e26e 100644
--- a/src/private/qquickstyleitem.cpp
+++ b/src/private/qquickstyleitem.cpp
@@ -318,7 +318,6 @@ void QQuickStyleItem::initStyleOption()
         if (!m_styleoption)
             m_styleoption = new QStyleOptionTab();
 
-
         QStyleOptionTab *opt = qstyleoption_cast<QStyleOptionTab*>(m_styleoption);
         opt->text = text();
 
@@ -396,6 +395,7 @@ void QQuickStyleItem::initStyleOption()
         QStyleOptionMenuItem *opt = qstyleoption_cast<QStyleOptionMenuItem*>(m_styleoption);
         opt->text = text();
         opt->menuItemType = QStyleOptionMenuItem::Normal;
+        setProperty("_q_showUnderlined", m_hints["showUnderlined"].toBool());
 
         if (const QFont *font = QGuiApplicationPrivate::platformTheme()->font(QPlatformTheme::MenuBarFont)) {
             opt->font = *font;
@@ -443,6 +443,7 @@ void QQuickStyleItem::initStyleOption()
             }
             if (m_properties["icon"].canConvert<QIcon>())
                 opt->icon = m_properties["icon"].value<QIcon>();
+            setProperty("_q_showUnderlined", m_hints["showUnderlined"].toBool());
 
             if (const QFont *font = QGuiApplicationPrivate::platformTheme()->font(m_itemType == ComboBoxItem ? QPlatformTheme::ComboMenuItemFont : QPlatformTheme::MenuFont)) {
                 opt->font = *font;
diff --git a/src/styles/Desktop/MenuBarStyle.qml b/src/styles/Desktop/MenuBarStyle.qml
index 291df0fb..f1d7b353 100644
--- a/src/styles/Desktop/MenuBarStyle.qml
+++ b/src/styles/Desktop/MenuBarStyle.qml
@@ -51,6 +51,8 @@ Style {
         width: implicitWidth + 2 * (pixelMetric("menubarhmargin") + pixelMetric("menubarpanelwidth"))
         height: implicitHeight + 2 * (pixelMetric("menubarvmargin") + pixelMetric("menubarpanelwidth"))
                 + pixelMetric("spacebelowmenubar")
+
+        Accessible.role: Accessible.MenuBar
     }
 
     property Component menuItem: StyleItem {
@@ -66,5 +68,10 @@ Style {
         enabled: menuItem.enabled
         selected: (parent && parent.selected) || sunken
         sunken: parent && parent.sunken
+
+        hints: { "showUnderlined": showUnderlined }
+
+        Accessible.role: Accessible.MenuItem
+        Accessible.name: StyleHelpers.removeMnemonics(text)
     }
 }
diff --git a/src/styles/Desktop/MenuStyle.qml b/src/styles/Desktop/MenuStyle.qml
index 960a163d..d659c25d 100644
--- a/src/styles/Desktop/MenuStyle.qml
+++ b/src/styles/Desktop/MenuStyle.qml
@@ -65,6 +65,8 @@ Style {
             }
             color: __syspal.window
         }
+
+        Accessible.role: Accessible.PopupMenu
     }
 
     property Component menuItem: StyleItem {
@@ -81,6 +83,8 @@ Style {
         selected: !!parent && parent.selected
         on: !!menuItem && !!menuItem["checkable"] && menuItem.checked
 
+        hints: { "showUnderlined": showUnderlined }
+
         properties: {
             "checkable": !!menuItem && !!menuItem["checkable"],
             "exclusive": !!menuItem && !!menuItem["exclusiveGroup"],
@@ -88,5 +92,8 @@ Style {
             "isSubmenu": isSubmenu,
             "icon": !!menuItem && menuItem.__icon
         }
+
+        Accessible.role: Accessible.MenuItem
+        Accessible.name: StyleHelpers.removeMnemonics(text)
     }
 }