[ComboTabBar] Correctly switch tabs when closing last tab in tabbar

Also remove custom logic for SelectPreviousTab on tab remove and use
only the QTabBar's selectionBehaviorOnRemove

Fix 1 for #1322

src/lib/tabwidget/combotabbar.cpp

@@ -49,8 +49,8 @@ ComboTabBar::ComboTabBar(QWidget* parent)
 {
     QObject::setObjectName(QSL("tabbarwidget"));
 
-    m_mainTabBar = new TabBarHelper(this);
-    m_pinnedTabBar = new TabBarHelper(this);
+    m_mainTabBar = new TabBarHelper(/*pinnedTabBar*/ false, this);
+    m_pinnedTabBar = new TabBarHelper(/*pinnedTabBar*/ true, this);
     m_mainTabBarWidget = new TabBarScrollWidget(m_mainTabBar, this);
     m_pinnedTabBarWidget = new TabBarScrollWidget(m_pinnedTabBar, this);
 
@@ -915,7 +915,7 @@ void ComboTabBar::leaveEvent(QEvent* event)
 }
 
 
-TabBarHelper::TabBarHelper(ComboTabBar* comboTabBar)
+TabBarHelper::TabBarHelper(bool pinnedTabBar, ComboTabBar* comboTabBar)
     : QTabBar(comboTabBar)
     , m_comboTabBar(comboTabBar)
     , m_scrollArea(0)
@@ -923,6 +923,7 @@ TabBarHelper::TabBarHelper(ComboTabBar* comboTabBar)
     , m_pressedGlobalX(-1)
     , m_dragInProgress(false)
     , m_activeTabBar(false)
+    , m_pinnedTabBar(pinnedTabBar)
     , m_useFastTabSizeHint(false)
     , m_bluredBackground(false)
 {
@@ -955,6 +956,17 @@ void TabBarHelper::setActiveTabBar(bool activate)
 {
     if (m_activeTabBar != activate) {
         m_activeTabBar = activate;
+
+        // If the last tab in a tabbar is closed, the selection jumps to the other
+        // tabbar. The stacked widget automatically selects the next tab, which is
+        // either the last tab in pinned tabbar or the first one in main tabbar.
+
+        if (!m_activeTabBar) {
+            m_comboTabBar->m_blockCurrentChangedSignal = true;
+            setCurrentIndex(m_pinnedTabBar ? count() - 1 : 0);
+            m_comboTabBar->m_blockCurrentChangedSignal = false;
+        }
+
         update();
     }
 }
@@ -963,9 +975,8 @@ void TabBarHelper::removeTab(int index)
 {
     // Removing tab in inactive tabbar will change current index and thus
     // changing active tabbar, which is really not wanted.
-    if (!m_activeTabBar) {
+    if (!m_activeTabBar)
         m_comboTabBar->m_blockCurrentChangedSignal = true;
-    }
 
     QTabBar::removeTab(index);
 

src/lib/tabwidget/combotabbar.h

@@ -212,7 +212,7 @@ class QUPZILLA_EXPORT TabBarHelper : public QTabBar
     Q_OBJECT
 
 public:
-    explicit TabBarHelper(ComboTabBar* comboTabBar);
+    explicit TabBarHelper(bool pinnedTabBar, ComboTabBar* comboTabBar);
 
     void setTabButton(int index, QTabBar::ButtonPosition position, QWidget* widget);
 
@@ -252,6 +252,7 @@ private:
     int m_pressedGlobalX;
     bool m_dragInProgress;
     bool m_activeTabBar;
+    bool m_pinnedTabBar;
     bool m_useFastTabSizeHint;
     bool m_bluredBackground;
 };

src/lib/tabwidget/tabwidget.cpp

@@ -116,7 +116,6 @@ TabWidget::TabWidget(BrowserWindow* window, QWidget* parent)
     , m_closedTabsManager(new ClosedTabsManager)
     , m_lastTabIndex(-1)
     , m_lastBackgroundTabIndex(-1)
-    , m_isClosingToLastTabIndex(false)
 {
     setObjectName(QSL("tabwidget"));
 
@@ -389,10 +388,6 @@ int TabWidget::addView(const LoadRequest &req, const QString &title, const Qz::N
         m_window->locationBar()->setFocus();
     }
 
-    if (openFlags & Qz::NT_SelectedTab || openFlags & Qz::NT_NotSelectedTab) {
-        m_isClosingToLastTabIndex = true;
-    }
-
     if (openFlags & Qz::NT_NotSelectedTab) {
         WebTab* currentWebTab = weTab();
         // Workarounding invalid QWebPage::viewportSize() until QWebView is shown
@@ -485,9 +480,6 @@ void TabWidget::closeTab(int index, bool force)
     disconnect(webView, SIGNAL(changed()), this, SIGNAL(changed()));
     disconnect(webView, SIGNAL(ipChanged(QString)), m_window->ipLabel(), SLOT(setText(QString)));
 
-    if (m_isClosingToLastTabIndex && m_lastTabIndex < count() && index == currentIndex())
-        setCurrentIndex(m_lastTabIndex);
-
     m_lastBackgroundTabIndex = -1;
 
     if (m_menuTabs->isVisible()) {
@@ -508,7 +500,6 @@ void TabWidget::currentTabChanged(int index)
     if (!validIndex(index))
         return;
 
-    m_isClosingToLastTabIndex = m_lastBackgroundTabIndex == index;
     m_lastBackgroundTabIndex = -1;
     m_lastTabIndex = index;
 
@@ -529,7 +520,6 @@ void TabWidget::tabMoved(int before, int after)
     Q_UNUSED(before)
     Q_UNUSED(after)
 
-    m_isClosingToLastTabIndex = false;
     m_lastBackgroundTabIndex = -1;
     m_lastTabIndex = before;
 }
@@ -642,10 +632,6 @@ void TabWidget::detachTab(int index)
 
     BrowserWindow* window = mApp->createWindow(Qz::BW_NewWindow);
     window->setStartTab(tab);
-
-    if (m_isClosingToLastTabIndex && m_lastTabIndex < count() && index == currentIndex()) {
-        setCurrentIndex(m_lastTabIndex);
-    }
 }
 
 int TabWidget::duplicateTab(int index)

src/lib/tabwidget/tabwidget.h

@@ -155,7 +155,6 @@ private:
 
     int m_lastTabIndex;
     int m_lastBackgroundTabIndex;
-    bool m_isClosingToLastTabIndex;
 
     bool m_dontCloseWithOneTab;
     bool m_showClosedTabsButton;