Disable tabs menu button when only single tab exists in a Dock area (#111)

src/DockAreaTabBar.cpp

@@ -343,6 +343,7 @@ void CDockAreaTabBar::insertTab(int Index, CDockWidgetTab* Tab)
 	connect(Tab, SIGNAL(closeRequested()), this, SLOT(onTabCloseRequested()));
 	connect(Tab, SIGNAL(closeOtherTabsRequested()), this, SLOT(onCloseOtherTabsRequested()));
 	connect(Tab, SIGNAL(moved(const QPoint&)), this, SLOT(onTabWidgetMoved(const QPoint&)));
+	connect(Tab, SIGNAL(elidedChanged(bool)), this, SIGNAL(elidedChanged(bool)));
 	Tab->installEventFilter(this);
 	emit tabInserted(Index);
 	if (Index <= d->CurrentIndex || d->CurrentIndex == -1)
@@ -562,7 +563,6 @@ void CDockAreaTabBar::onTabWidgetMoved(const QPoint& GlobalPos)
 	}
 }
 
-
 //===========================================================================
 void CDockAreaTabBar::closeTab(int Index)
 {

src/DockAreaTabBar.h

@@ -239,6 +239,11 @@ signals:
 	 * This signal is emitted if a tab has been inserted
 	 */
 	void tabInserted(int index);
+
+	/**
+	 * This signal is emitted when a tab title elide state has been changed
+	 */
+	void elidedChanged(bool elided);
 }; // class CDockAreaTabBar
 } // namespace ads
 //-----------------------------------------------------------------------------

src/DockAreaTitleBar.cpp

@@ -151,10 +151,11 @@ protected:
 		if(QEvent::EnabledChange == ev->type() && HideWhenDisabled)
 		{
 			// force setVisible() call 
-			setVisible(isEnabled());
+			// Calling setVisible() directly here doesn't work well when button is expected to be shown first time
+			QMetaObject::invokeMethod(this, "setVisible", Qt::QueuedConnection, Q_ARG(bool, isEnabled()));
 		}
 
-		return Super::event(ev);;
+		return Super::event(ev);
 	}
 };
 
@@ -232,6 +233,7 @@ void DockAreaTitleBarPrivate::createTabBar()
 	_this->connect(TabBar, SIGNAL(tabMoved(int, int)), SLOT(markTabsMenuOutdated()));
 	_this->connect(TabBar, SIGNAL(currentChanged(int)), SLOT(onCurrentTabChanged(int)));
 	_this->connect(TabBar, SIGNAL(tabBarClicked(int)), SIGNAL(tabBarClicked(int)));
+	_this->connect(TabBar, SIGNAL(elidedChanged(bool)), SLOT(markTabsMenuOutdated()));
 
 	TabBar->setContextMenuPolicy(Qt::CustomContextMenu);
 	_this->connect(TabBar, SIGNAL(customContextMenuRequested(const QPoint&)),
@@ -286,14 +288,31 @@ CDockAreaTabBar* CDockAreaTitleBar::tabBar() const
 	return d->TabBar;
 }
 
-
 //============================================================================
 void CDockAreaTitleBar::markTabsMenuOutdated()
 {
+	if(DockAreaTitleBarPrivate::testConfigFlag(CDockManager::DockAreaDynamicTabsMenuButtonVisibility))
+	{
+		bool hasElidedTabTitle = false;
+		for (int i = 0; i < d->TabBar->count(); ++i)
+		{
+			if (!d->TabBar->isTabOpen(i))
+			{
+				continue;
+			}
+			CDockWidgetTab* Tab = d->TabBar->tab(i);
+			if(Tab->isTitleElided())
+			{
+				hasElidedTabTitle = true;
+				break;
+			}
+		}
+		bool visible = (hasElidedTabTitle && (d->TabBar->count() > 1));
+		QMetaObject::invokeMethod(d->TabsMenuButton, "setVisible", Qt::QueuedConnection, Q_ARG(bool, visible));
+	}
 	d->MenuOutdated = true;
 }
 
-
 //============================================================================
 void CDockAreaTitleBar::onTabsMenuAboutToShow()
 {

src/DockManager.h

@@ -145,7 +145,7 @@ public:
 	{
 		ActiveTabHasCloseButton = 0x0001,    //!< If this flag is set, the active tab in a tab area has a close button
 		DockAreaHasCloseButton = 0x0002,     //!< If the flag is set each dock area has a close button
-		DockAreaCloseButtonClosesTab = 0x0004,//!< If the flag is set, the dock area close button closes the active tab, if not set, it closes the complete cock area
+		DockAreaCloseButtonClosesTab = 0x0004,//!< If the flag is set, the dock area close button closes the active tab, if not set, it closes the complete dock area
 		OpaqueSplitterResize = 0x0008, //!< See QSplitter::setOpaqueResize() documentation
 		XmlAutoFormattingEnabled = 0x0010,//!< If enabled, the XML writer automatically adds line-breaks and indentation to empty sections between elements (ignorable whitespace).
 		XmlCompressionEnabled = 0x0020,//!< If enabled, the XML output will be compressed and is not human readable anymore
@@ -156,10 +156,11 @@ public:
 		DragPreviewIsDynamic = 0x0400,///< If opaque undocking is disabled, this flag defines the behavior of the drag preview window, if this flag is enabled, the preview will be adjusted dynamically to the drop area
 		DragPreviewShowsContentPixmap = 0x0800,///< If opaque undocking is disabled, the created drag preview window shows a copy of the content of the dock widget / dock are that is dragged
 		DragPreviewHasWindowFrame = 0x1000,///< If opaque undocking is disabled, then this flag configures if the drag preview is frameless or looks like a real window
-        AlwaysShowTabs = 0x2000,///< If this option is enabled, the tab of a dock widget is always displayed - even if it is the only visible dock widget in a floating widget.
-        DockAreaHasUndockButton = 0x4000,     //!< If the flag is set each dock area has an undock button
-        DockAreaHasTabsMenuButton = 0x8000,     //!< If the flag is set each dock area has a tabs menu button
-        DockAreaHideDisabledButtons = 0x10000,    //!< If the flag is set disabled dock area buttons will not appear on the tollbar at all (enabling them will bring them back)
+		AlwaysShowTabs = 0x2000,///< If this option is enabled, the tab of a dock widget is always displayed - even if it is the only visible dock widget in a floating widget.
+		DockAreaHasUndockButton = 0x4000,     //!< If the flag is set each dock area has an undock button
+		DockAreaHasTabsMenuButton = 0x8000,     //!< If the flag is set each dock area has a tabs menu button
+		DockAreaHideDisabledButtons = 0x10000,    //!< If the flag is set disabled dock area buttons will not appear on the tollbar at all (enabling them will bring them back)
+		DockAreaDynamicTabsMenuButtonVisibility = 0x20000,     //!< If the flag is set dock area will disable a tabs menu button when there is only one tab in the area
 
 
         DefaultDockAreaButtons = DockAreaHasCloseButton

src/DockWidgetTab.cpp

@@ -170,6 +170,8 @@ void DockWidgetTabPrivate::createLayout()
 	TitleLabel->setText(DockWidget->windowTitle());
 	TitleLabel->setObjectName("dockWidgetTabLabel");
 	TitleLabel->setAlignment(Qt::AlignCenter);
+	_this->connect(TitleLabel, SIGNAL(elidedChanged(bool)), SIGNAL(elidedChanged(bool)));
+
 
 	CloseButton = createCloseButton();
 	CloseButton->setObjectName("tabCloseButton");
@@ -556,6 +558,11 @@ void CDockWidgetTab::setText(const QString& title)
 	d->TitleLabel->setText(title);
 }
 
+bool CDockWidgetTab::isTitleElided() const
+{
+	return d->TitleLabel->isElided();
+}
+
 
 
 //============================================================================

src/DockWidgetTab.h

@@ -132,6 +132,11 @@ public:
 	 */
 	void setText(const QString& title);
 
+	/**
+	 * Returns true if text is elided on the tab's title
+	 */
+	bool isTitleElided() const;
+
 	/**
 	 * This function returns true if the assigned dock widget is closable
 	 */
@@ -152,6 +157,7 @@ signals:
 	void closeRequested();
 	void closeOtherTabsRequested();
 	void moved(const QPoint& GlobalPos);
+	void elidedChanged(bool elided);
 }; // class DockWidgetTab
 }
  // namespace ads

src/ElidingLabel.cpp

@@ -41,6 +41,7 @@ struct ElidingLabelPrivate
 	CElidingLabel* _this;
 	Qt::TextElideMode ElideMode = Qt::ElideNone;
 	QString Text;
+	bool IsElided = false;
 
 	ElidingLabelPrivate(CElidingLabel* _public) : _this(_public) {}
 
@@ -69,6 +70,12 @@ void ElidingLabelPrivate::elideText(int Width)
     {
     	str = Text.at(0);
     }
+    bool WasElided = IsElided;
+    IsElided = str != Text;
+    if(IsElided != WasElided)
+    {
+        emit _this->elidedChanged(IsElided);
+    }
     _this->QLabel::setText(str);
 }
 
@@ -113,6 +120,12 @@ void CElidingLabel::setElideMode(Qt::TextElideMode mode)
 	d->elideText(size().width());
 }
 
+//============================================================================
+bool CElidingLabel::isElided() const
+{
+	return d->IsElided;
+}
+
 
 //============================================================================
 void CElidingLabel::mouseReleaseEvent(QMouseEvent* event)

src/ElidingLabel.h

@@ -73,6 +73,10 @@ public:
 	 */
 	void setElideMode(Qt::TextElideMode mode);
 
+	/**
+	 * This function indicates whether the text on this label is currently elided
+	 */
+	bool isElided() const;
 
 public: // reimplements QLabel ----------------------------------------------
 	virtual QSize minimumSizeHint() const override;
@@ -91,6 +95,11 @@ signals:
 	 * This signal is emitted if the user does a double click on the label
 	 */
 	void doubleClicked();
+    
+    /**
+	 * This signal is emitted when isElided() state of this label is changed
+	 */
+	void elidedChanged(bool elided);
 }; //class CElidingLabel
 
 } // namespace QtLabb