Add KHamburgerMenu support

src/kmail_part.rc

@@ -2,7 +2,7 @@
      the same menu entries at the same place in KMail and Kontact  -->
 
 <!DOCTYPE gui>
-<gui version="548" name="kmmainwin" translationDomain="kmail">
+<gui version="549" name="kmmainwin" translationDomain="kmail">
  <MenuBar>
   <Menu noMerge="1" name="file" >
    <text>&amp;File</text>
@@ -347,5 +347,7 @@
   <Action name="create_todo"/>
   <Separator/>
   <ActionList name="kmail_toolbar_actions"/> 
+  <Spacer/>
+  <Action name="hamburger_menu"/>
  </ToolBar>
 </gui>

src/kmmainwin.cpp

@@ -15,6 +15,7 @@
 #include <PimCommon/BroadcastStatus>
 
 #include <KConfigGroup>
+#include <KToolBar>
 #include <QApplication>
 #include <QStatusBar>
 #include <QTimer>
@@ -55,7 +56,17 @@ KMMainWin::KMMainWin(QWidget *)
 
     KStandardAction::keyBindings(this, &KMMainWin::slotConfigureShortcuts, actionCollection());
 
-    mHideMenuBarAction = KStandardAction::showMenubar(this, &KMMainWin::slotToggleMenubar, actionCollection());
+    mShowMenuBarAction = KStandardAction::showMenubar(this, &KMMainWin::slotToggleMenubar, actionCollection());
+    mHamburgerMenu = KStandardAction::hamburgerMenu(nullptr, nullptr, actionCollection());
+    mHamburgerMenu->setShowMenuBarAction(mShowMenuBarAction);
+    mHamburgerMenu->setMenuBar(menuBar());
+    connect(mHamburgerMenu, &KHamburgerMenu::aboutToShowMenu, this, [this]() {
+        this->updateHamburgerMenu();
+        // Immediately disconnect. We only need to run this once, but on demand.
+        // NOTE: The nullptr at the end disconnects all connections between
+        // q and mHamburgerMenu's aboutToShowMenu signal.
+        disconnect(mHamburgerMenu, &KHamburgerMenu::aboutToShowMenu, this, nullptr);
+    });
 
     KStandardAction::quit(this, &KMMainWin::slotQuit, actionCollection());
     createGUI(QStringLiteral("kmmainwin.rc"));
@@ -68,7 +79,7 @@ KMMainWin::KMMainWin(QWidget *)
     connect(mKMMainWidget, &KMMainWidget::captionChangeRequest, this, qOverload<const QString &>(&KMainWindow::setCaption));
 
     mKMMainWidget->updateQuickSearchLineText();
-    mHideMenuBarAction->setChecked(KMailSettings::self()->showMenuBar());
+    mShowMenuBarAction->setChecked(KMailSettings::self()->showMenuBar());
     slotToggleMenubar(true);
 }
 
@@ -79,6 +90,24 @@ KMMainWin::~KMMainWin()
     disconnect(PimCommon::BroadcastStatus::instance(), &PimCommon::BroadcastStatus::statusMsg, this, nullptr);
 }
 
+void KMMainWin::updateHamburgerMenu()
+{
+    QMenu *menu = new QMenu;
+    menu->addAction(actionCollection()->action(QLatin1String(KStandardAction::name(KStandardAction::Open))));
+    menu->addAction(actionCollection()->action(QLatin1String(KStandardAction::name(KStandardAction::OpenRecent))));
+    menu->addAction(actionCollection()->action(QLatin1String(KStandardAction::name(KStandardAction::Save))));
+    menu->addAction(actionCollection()->action(QLatin1String(KStandardAction::name(KStandardAction::SaveAs))));
+    menu->addAction(actionCollection()->action(QLatin1String(KStandardAction::name(KStandardAction::Print))));
+    menu->addSeparator();
+    menu->addAction(actionCollection()->action(QStringLiteral("check_mail")));
+    menu->addAction(actionCollection()->action(QStringLiteral("check_mail_in")));
+    menu->addAction(actionCollection()->action(QStringLiteral("send_queued")));
+    menu->addAction(actionCollection()->action(QStringLiteral("send_queued_via")));
+    menu->addSeparator();
+    menu->addAction(actionCollection()->action(QLatin1String(KStandardAction::name(KStandardAction::Quit))));
+    mHamburgerMenu->setMenu(menu);
+}
+
 KMMainWidget *KMMainWin::mainKMWidget() const
 {
     return mKMMainWidget;
@@ -106,11 +135,11 @@ void KMMainWin::displayStatusMessage(const QString &aText)
 void KMMainWin::slotToggleMenubar(bool dontShowWarning)
 {
     if (menuBar()) {
-        if (mHideMenuBarAction->isChecked()) {
+        if (mShowMenuBarAction->isChecked()) {
             menuBar()->show();
         } else {
-            if (!dontShowWarning) {
-                const QString accel = mHideMenuBarAction->shortcut().toString();
+            if (!dontShowWarning && (!toolBar()->isVisible() || !toolBar()->actions().contains(mHamburgerMenu))) {
+                const QString accel = mShowMenuBarAction->shortcut().toString();
                 KMessageBox::information(this,
                                          i18n("<qt>This will hide the menu bar completely."
                                               " You can show it again by typing %1.</qt>",
@@ -120,7 +149,7 @@ void KMMainWin::slotToggleMenubar(bool dontShowWarning)
             }
             menuBar()->hide();
         }
-        KMailSettings::self()->setShowMenuBar(mHideMenuBarAction->isChecked());
+        KMailSettings::self()->setShowMenuBar(mShowMenuBarAction->isChecked());
     }
 }
 

src/kmmainwin.h

@@ -14,6 +14,7 @@
 class KMMainWidget;
 class KToggleAction;
 class QLabel;
+class KHamburgerMenu;
 namespace KPIM
 {
 class ProgressStatusBarWidget;
@@ -53,10 +54,12 @@ protected Q_SLOTS:
 private:
     void slotConfigureShortcuts();
     void slotToggleMenubar(bool dontShowWarning);
+    void updateHamburgerMenu();
     KPIM::ProgressStatusBarWidget *mProgressBar = nullptr;
     KMMainWidget *mKMMainWidget = nullptr;
-    KToggleAction *mHideMenuBarAction = nullptr;
+    KToggleAction *mShowMenuBarAction = nullptr;
     QLabel *mMessageLabel = nullptr;
+    KHamburgerMenu *mHamburgerMenu = nullptr;
     bool mReallyClose = false;
 };
 

src/kmmainwin.rc

@@ -2,7 +2,7 @@
      the same menu entries at the same place in KMail and Kontact  -->
 
 <!DOCTYPE gui>
-<gui version="548" name="kmmainwin" translationDomain="kmail">
+<gui version="549" name="kmmainwin" translationDomain="kmail">
  <MenuBar>
   <Menu noMerge="1" name="file" >
    <text>&amp;File</text>
@@ -347,5 +347,7 @@
   <Action name="create_todo"/>
   <Separator/>
   <ActionList name="kmail_toolbar_actions"/> 
+  <Spacer/>
+  <Action name="hamburger_menu"/>
  </ToolBar>
 </gui>