fix screen count alignment

REVIEW: 110119

screens.cpp

@@ -36,10 +36,11 @@ Screens::Screens(QObject *parent)
     , m_count(0)
     , m_current(0)
     , m_currentFollowsMouse(false)
-    , m_changedTimer(new QTimer(this))
+    , m_changedTimer(new ScreenCountTimer(this))
 {
     m_changedTimer->setSingleShot(true);
     m_changedTimer->setInterval(100);
+    connect(m_changedTimer, SIGNAL(timeout()), SLOT(updateCount()));
     connect(m_changedTimer, SIGNAL(timeout()), SIGNAL(changed()));
 
     Settings settings;
@@ -115,19 +116,26 @@ int Screens::current() const
     return m_current;
 }
 
-void Screens::startChangedTimer()
+ScreenCountTimer::ScreenCountTimer(QObject * parent) : QTimer(parent)
 {
-    m_changedTimer->start();
+}
+
+void ScreenCountTimer::finish()
+{
+    if (isActive()) {
+        stop();
+        Screens::self()->updateCount();
+        QMetaObject::invokeMethod(Screens::self(), "changed", Qt::QueuedConnection);
+    }
 }
 
 DesktopWidgetScreens::DesktopWidgetScreens(QObject *parent)
     : Screens(parent)
     , m_desktop(QApplication::desktop())
 {
-    connect(m_desktop, SIGNAL(screenCountChanged(int)), SLOT(setCount(int)));
     connect(m_desktop, SIGNAL(screenCountChanged(int)), SLOT(startChangedTimer()));
     connect(m_desktop, SIGNAL(resized(int)), SLOT(startChangedTimer()));
-    setCount(m_desktop->screenCount());
+    updateCount();
 }
 
 DesktopWidgetScreens::~DesktopWidgetScreens()
@@ -136,12 +144,19 @@ DesktopWidgetScreens::~DesktopWidgetScreens()
 
 QRect DesktopWidgetScreens::geometry(int screen) const
 {
+    finishChangedTimer();
     return m_desktop->screenGeometry(screen);
 }
 
 int DesktopWidgetScreens::number(const QPoint &pos) const
 {
+    finishChangedTimer();
     return m_desktop->screenNumber(pos);
 }
 
+void DesktopWidgetScreens::updateCount()
+{
+    setCount(m_desktop->screenCount());
+}
+
 } // namespace

screens.h

@@ -27,14 +27,23 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 // Qt includes
 #include <QObject>
 #include <QRect>
+#include <QTimer>
 
 class QDesktopWidget;
-class QTimer;
 
 namespace KWin
 {
 class Client;
 
+class ScreenCountTimer : public QTimer {
+    public:
+        ScreenCountTimer(QObject * parent = 0);
+        /**
+         * if isActive, stop AND emit timeout()
+         */
+        void finish();
+};
+
 class Screens : public QObject
 {
     Q_OBJECT
@@ -76,15 +85,20 @@ Q_SIGNALS:
      **/
     void changed();
 
+protected:
+    void finishChangedTimer() const;
+
 protected Q_SLOTS:
+    friend class ScreenCountTimer;
     void setCount(int count);
     void startChangedTimer();
+    virtual void updateCount() = 0;
 
 private:
     int m_count;
     int m_current;
     bool m_currentFollowsMouse;
-    QTimer *m_changedTimer;
+    ScreenCountTimer *m_changedTimer;
     KSharedConfig::Ptr m_config;
 
     KWIN_SINGLETON(Screens)
@@ -98,6 +112,8 @@ public:
     virtual ~DesktopWidgetScreens();
     virtual QRect geometry(int screen) const;
     virtual int number(const QPoint &pos) const;
+protected Q_SLOTS:
+    void updateCount();
 
 private:
     QDesktopWidget *m_desktop;
@@ -115,12 +131,24 @@ int Screens::count() const
     return m_count;
 }
 
+inline
+void Screens::finishChangedTimer() const
+{
+    const_cast<ScreenCountTimer*>(m_changedTimer)->finish();
+}
+
 inline
 bool Screens::isCurrentFollowsMouse() const
 {
     return m_currentFollowsMouse;
 }
 
+inline
+void Screens::startChangedTimer()
+{
+    m_changedTimer->start();
+}
+
 inline
 Screens *screens()
 {