Rearranged the gesture code a bit for future native gestures on Windows.

Moved the code that subscribes to native gestures on Windows to a private
function in QWidget which will check which gestures the widget is subscribed to
and enable native gestures as requested.

Reviewed-by: trustme

3 files changed, 6 insertions, 28 deletions

diff --git a/src/gui/widgets/qabstractscrollarea.cpp b/src/gui/widgets/qabstractscrollarea.cpp
index dd92e17..e803afc 100644
--- a/src/gui/widgets/qabstractscrollarea.cpp
+++ b/src/gui/widgets/qabstractscrollarea.cpp
@@ -296,32 +296,6 @@ void QAbstractScrollAreaPrivate::init()
     layoutChildren();
 }
 
-void QAbstractScrollAreaPrivate::setupGestures()
-{
-#ifdef Q_OS_WIN
-    if (!viewport)
-        return;
-    QApplicationPrivate* getQApplicationPrivateInternal();
-    QApplicationPrivate *qAppPriv = getQApplicationPrivateInternal();
-    bool needh = (hbarpolicy == Qt::ScrollBarAlwaysOn
-                  || (hbarpolicy == Qt::ScrollBarAsNeeded && hbar->minimum() < hbar->maximum()));
-
-    bool needv = (vbarpolicy == Qt::ScrollBarAlwaysOn
-                  || (vbarpolicy == Qt::ScrollBarAsNeeded && vbar->minimum() < vbar->maximum()));
-    if (qAppPriv->SetGestureConfig && (needh || needv)) {
-        GESTURECONFIG gc[1];
-        gc[0].dwID = GID_PAN;
-        gc[0].dwWant = GC_PAN;
-        gc[0].dwBlock = 0;
-        if (needv && singleFingerPanEnabled)
-            gc[0].dwWant |= GC_PAN_WITH_SINGLE_FINGER_VERTICALLY;
-        if (needh && singleFingerPanEnabled)
-            gc[0].dwWant |= GC_PAN_WITH_SINGLE_FINGER_HORIZONTALLY;
-        qAppPriv->SetGestureConfig(viewport->winId(), 0, 1, gc, sizeof(gc));
-    }
-#endif // Q_OS_WIN
-}
-
 void QAbstractScrollAreaPrivate::layoutChildren()
 {
     Q_Q(QAbstractScrollArea);
@@ -1267,7 +1241,11 @@ void QAbstractScrollAreaPrivate::_q_vslide(int y)
 void QAbstractScrollAreaPrivate::_q_showOrHideScrollBars()
 {
     layoutChildren();
-    setupGestures();
+#ifdef Q_OS_WIN
+    // Need to re-subscribe to gestures as the content changes to make sure we
+    // enable/disable panning when needed.
+    winSetupGestures();
+#endif // Q_OS_WIN
 }
 
 QPoint QAbstractScrollAreaPrivate::contentsOffset() const
diff --git a/src/gui/widgets/qabstractscrollarea.h b/src/gui/widgets/qabstractscrollarea.h
index 3ec41d1..c7441c1 100644
--- a/src/gui/widgets/qabstractscrollarea.h
+++ b/src/gui/widgets/qabstractscrollarea.h
@@ -130,6 +130,7 @@ private:
     Q_PRIVATE_SLOT(d_func(), void _q_showOrHideScrollBars())
 
     friend class QStyleSheetStyle;
+    friend class QWidgetPrivate;
 };
 
 #endif // QT_NO_SCROLLAREA
diff --git a/src/gui/widgets/qabstractscrollarea_p.h b/src/gui/widgets/qabstractscrollarea_p.h
index aef8ac5..9a6b923 100644
--- a/src/gui/widgets/qabstractscrollarea_p.h
+++ b/src/gui/widgets/qabstractscrollarea_p.h
@@ -103,7 +103,6 @@ public:
 #ifdef Q_WS_WIN
     bool singleFingerPanEnabled;
 #endif
-    void setupGestures();
 };
 
 class QAbstractScrollAreaFilter : public QObject