Enable pan gesture on all QAbstractScrollArea-based widgets.

Two-finger panning will work on all QAbstractScrollArea based widgets, however
single-finger panning will be enabled only on some special widgets that always
wants it - for example we don't want it on QGraphicsView, and we might want it
on itemviews *sometimes*.

Reviewed-by: trustme

7 files changed, 40 insertions, 29 deletions

diff --git a/src/gui/kernel/qwidget_win.cpp b/src/gui/kernel/qwidget_win.cpp
index 6647f3f..d8bee55 100644
--- a/src/gui/kernel/qwidget_win.cpp
+++ b/src/gui/kernel/qwidget_win.cpp
@@ -2056,6 +2056,8 @@ void QWidgetPrivate::registerTouchWindow()
 void QWidgetPrivate::winSetupGestures()
 {
     Q_Q(QWidget);
+    if (!q)
+        return;
     QApplicationPrivate *qAppPriv = getQApplicationPrivateInternal();
     bool needh = false;
     bool needv = false;
@@ -2097,6 +2099,7 @@ void QWidgetPrivate::winSetupGestures()
             gc[1].dwWant = GC_ZOOM;
             gc[1].dwBlock = 0;
         }
+        Q_ASSERT(winid);
         qAppPriv->SetGestureConfig(winid, 0, sizeof(gc)/sizeof(gc[0]), gc, sizeof(gc[0]));
     }
 }
diff --git a/src/gui/widgets/qabstractscrollarea.cpp b/src/gui/widgets/qabstractscrollarea.cpp
index e803afc..f6c1892 100644
--- a/src/gui/widgets/qabstractscrollarea.cpp
+++ b/src/gui/widgets/qabstractscrollarea.cpp
@@ -159,7 +159,7 @@ QT_BEGIN_NAMESPACE
 QAbstractScrollAreaPrivate::QAbstractScrollAreaPrivate()
     :hbar(0), vbar(0), vbarpolicy(Qt::ScrollBarAsNeeded), hbarpolicy(Qt::ScrollBarAsNeeded),
      viewport(0), cornerWidget(0), left(0), top(0), right(0), bottom(0),
-     xoffset(0), yoffset(0), viewportFilter(0)
+     xoffset(0), yoffset(0), viewportFilter(0), panGesture(0)
 #ifdef Q_WS_WIN
      , singleFingerPanEnabled(false)
 #endif
@@ -294,7 +294,18 @@ void QAbstractScrollAreaPrivate::init()
     q->setFrameStyle(QFrame::StyledPanel | QFrame::Sunken);
     q->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
     layoutChildren();
+
+    panGesture = new QPanGesture(q);
+    QObject::connect(panGesture, SIGNAL(triggered()), q, SLOT(_q_gestureTriggered()));
+}
+
+#ifdef Q_WS_WIN
+void QAbstractScrollAreaPrivate::setSingleFingerPanEnabled(bool on)
+{
+    singleFingerPanEnabled = on;
+    winSetupGestures();
 }
+#endif // Q_WS_WIN
 
 void QAbstractScrollAreaPrivate::layoutChildren()
 {
@@ -1310,6 +1321,25 @@ void QAbstractScrollArea::setupViewport(QWidget *viewport)
     Q_UNUSED(viewport);
 }
 
+void QAbstractScrollAreaPrivate::_q_gestureTriggered()
+{
+    Q_Q(QAbstractScrollArea);
+    QPanGesture *g = qobject_cast<QPanGesture*>(q->sender());
+    if (!g)
+        return;
+    QScrollBar *hBar = q->horizontalScrollBar();
+    QScrollBar *vBar = q->verticalScrollBar();
+    QSize delta = g->lastOffset();
+    if (!delta.isNull()) {
+        if (QApplication::isRightToLeft())
+            delta.rwidth() *= -1;
+        int newX = hBar->value() - delta.width();
+        int newY = vBar->value() - delta.height();
+        hbar->setValue(newX);
+        vbar->setValue(newY);
+    }
+}
+
 QT_END_NAMESPACE
 
 #include "moc_qabstractscrollarea.cpp"
diff --git a/src/gui/widgets/qabstractscrollarea.h b/src/gui/widgets/qabstractscrollarea.h
index c7441c1..9178629 100644
--- a/src/gui/widgets/qabstractscrollarea.h
+++ b/src/gui/widgets/qabstractscrollarea.h
@@ -128,6 +128,7 @@ private:
     Q_PRIVATE_SLOT(d_func(), void _q_hslide(int))
     Q_PRIVATE_SLOT(d_func(), void _q_vslide(int))
     Q_PRIVATE_SLOT(d_func(), void _q_showOrHideScrollBars())
+    Q_PRIVATE_SLOT(d_func(), void _q_gestureTriggered())
 
     friend class QStyleSheetStyle;
     friend class QWidgetPrivate;
diff --git a/src/gui/widgets/qabstractscrollarea_p.h b/src/gui/widgets/qabstractscrollarea_p.h
index 9a6b923..8011ed5 100644
--- a/src/gui/widgets/qabstractscrollarea_p.h
+++ b/src/gui/widgets/qabstractscrollarea_p.h
@@ -60,6 +60,7 @@ QT_BEGIN_NAMESPACE
 
 #ifndef QT_NO_SCROLLAREA
 
+class QPanGesture;
 class QScrollBar;
 class QAbstractScrollAreaScrollBarContainer;
 class Q_AUTOTEST_EXPORT QAbstractScrollAreaPrivate: public QFramePrivate
@@ -100,8 +101,11 @@ public:
     { return q_func()->viewportEvent(event); }
     QObject *viewportFilter;
 
+    virtual void _q_gestureTriggered();
+    QPanGesture *panGesture;
 #ifdef Q_WS_WIN
     bool singleFingerPanEnabled;
+    void setSingleFingerPanEnabled(bool on = true);
 #endif
 };
 
diff --git a/src/gui/widgets/qtextedit.cpp b/src/gui/widgets/qtextedit.cpp
index c095f5c..0a41d74 100644
--- a/src/gui/widgets/qtextedit.cpp
+++ b/src/gui/widgets/qtextedit.cpp
@@ -114,7 +114,7 @@ QTextEditPrivate::QTextEditPrivate()
     showCursorOnInitialShow = true;
     inDrag = false;
 #ifdef Q_WS_WIN
-    singleFingerPanEnabled = true;
+    setSingleFingerPanEnabled(true);
 #endif
 }
 
@@ -183,8 +183,6 @@ void QTextEditPrivate::init(const QString &html)
 #ifndef QT_NO_CURSOR
     viewport->setCursor(Qt::IBeamCursor);
 #endif
-    panGesture = new QPanGesture(q);
-    QObject::connect(panGesture, SIGNAL(triggered()), q, SLOT(_q_gestureTriggered()));
 }
 
 void QTextEditPrivate::_q_repaintContents(const QRectF &contentsRect)
@@ -2617,26 +2615,6 @@ void QTextEdit::ensureCursorVisible()
     d->control->ensureCursorVisible();
 }
 
-void QTextEditPrivate::_q_gestureTriggered()
-{
-    Q_Q(QTextEdit);
-    QPanGesture *g = qobject_cast<QPanGesture*>(q->sender());
-    if (!g)
-        return;
-    QScrollBar *hBar = q->horizontalScrollBar();
-    QScrollBar *vBar = q->verticalScrollBar();
-    QSize delta = g->lastOffset();
-    if (!delta.isNull()) {
-        if (QApplication::isRightToLeft())
-            delta.rwidth() *= -1;
-        int newX = hBar->value() - delta.width();
-        int newY = vBar->value() - delta.height();
-        hbar->setValue(newX);
-        vbar->setValue(newY);
-    }
-}
-
-
 /*!
     \enum QTextEdit::KeyboardAction
 
diff --git a/src/gui/widgets/qtextedit.h b/src/gui/widgets/qtextedit.h
index 9e10e07..617822a 100644
--- a/src/gui/widgets/qtextedit.h
+++ b/src/gui/widgets/qtextedit.h
@@ -414,7 +414,6 @@ private:
     Q_PRIVATE_SLOT(d_func(), void _q_currentCharFormatChanged(const QTextCharFormat &))
     Q_PRIVATE_SLOT(d_func(), void _q_adjustScrollbars())
     Q_PRIVATE_SLOT(d_func(), void _q_ensureVisible(const QRectF &))
-    Q_PRIVATE_SLOT(d_func(), void _q_gestureTriggered())
     friend class QTextEditControl;
     friend class QTextDocument;
     friend class QTextControl;
diff --git a/src/gui/widgets/qtextedit_p.h b/src/gui/widgets/qtextedit_p.h
index 249331e..3d14af6 100644
--- a/src/gui/widgets/qtextedit_p.h
+++ b/src/gui/widgets/qtextedit_p.h
@@ -70,7 +70,6 @@ QT_BEGIN_NAMESPACE
 #ifndef QT_NO_TEXTEDIT
 
 class QMimeData;
-class QPanGesture;
 class QTextEditPrivate : public QAbstractScrollAreaPrivate
 {
     Q_DECLARE_PUBLIC(QTextEdit)
@@ -129,9 +128,6 @@ public:
 
     QString anchorToScrollToWhenVisible;
 
-    void _q_gestureTriggered();
-    QPanGesture *panGesture;
-
 #ifdef QT_KEYPAD_NAVIGATION
     QBasicTimer deleteAllTimer;
 #endif