qtquick: Added TitleBar_qtquick::numDockWidgetsChanged() signal

In case the custom titlebar wants to do something with it.

src/controllers/TitleBar.cpp

@@ -44,6 +44,7 @@ TitleBar::TitleBar(Group *parent)
 {
     init();
     connect(m_group, &Group::numDockWidgetsChanged, this, &TitleBar::updateCloseButton);
+    connect(m_group, &Group::numDockWidgetsChanged, this, &TitleBar::numDockWidgetsChanged);
     connect(m_group, &Group::isFocusedChanged, this, &TitleBar::isFocusedChanged);
     connect(m_group, &Group::isInMainWindowChanged, this, &TitleBar::updateAutoHideButton);
 }
@@ -59,6 +60,8 @@ TitleBar::TitleBar(FloatingWindow *parent)
 {
     init();
     connect(m_floatingWindow, &FloatingWindow::numFramesChanged, this, &TitleBar::updateButtons);
+    connect(m_floatingWindow, &FloatingWindow::numFramesChanged, this,
+            &TitleBar::numDockWidgetsChanged);
     connect(m_floatingWindow, &FloatingWindow::windowStateChanged, this,
             &TitleBar::updateMaximizeButton);
     connect(m_floatingWindow, &FloatingWindow::activatedChanged, this, &TitleBar::isFocusedChanged);

src/controllers/TitleBar.h

@@ -113,6 +113,7 @@ public:
     bool floatButtonVisible() const;
     void setCloseButtonEnabled(bool);
     void setFloatButtonVisible(bool);
+
 Q_SIGNALS:
     void titleChanged();
     void iconChanged();
@@ -120,6 +121,7 @@ Q_SIGNALS:
     void closeButtonEnabledChanged(bool);
     void floatButtonVisibleChanged(bool);
     void floatButtonToolTipChanged(const QString &);
+    void numDockWidgetsChanged();
 
     /// @brief Emitted to tell the views to update their auto-hide button
     void autoHideButtonChanged(bool visible, bool enabled, TitleBarButtonType);

src/qtquick/views/TitleBar_qtquick.cpp

@@ -51,6 +51,8 @@ void TitleBar_qtquick::init()
             &TitleBar_qtquick::floatButtonVisibleChanged);
     connect(m_titleBar, &Controllers::TitleBar::floatButtonToolTipChanged, this,
             &TitleBar_qtquick::floatButtonToolTipChanged);
+    connect(m_titleBar, &Controllers::TitleBar::numDockWidgetsChanged, this,
+            &TitleBar_qtquick::numDockWidgetsChanged);
 }
 
 #ifdef DOCKS_DEVELOPER_MODE

src/qtquick/views/TitleBar_qtquick.h

@@ -85,6 +85,9 @@ Q_SIGNALS:
     void floatButtonVisibleChanged(bool);
     void floatButtonToolTipChanged(const QString &);
 
+    /// Emitted when the number of dock widgets under this titlebar changes
+    void numDockWidgetsChanged();
+
 protected:
     void init() override;