use touch events if possible

2 files changed, 88 insertions, 31 deletions

diff --git a/testapp/qscrollareakineticscroller.cpp b/testapp/qscrollareakineticscroller.cpp
index a1ed70d..0b37a16 100644
--- a/testapp/qscrollareakineticscroller.cpp
+++ b/testapp/qscrollareakineticscroller.cpp
@@ -94,7 +94,7 @@ public:
         : q_ptr(0)
         , area(0)
         , ignoreEvents(false)
-    {}
+    { }
 
     void init()
     {
diff --git a/touchy/qscrollareakineticscroller.cpp b/touchy/qscrollareakineticscroller.cpp
index 6702325..ad7a137 100644
--- a/touchy/qscrollareakineticscroller.cpp
+++ b/touchy/qscrollareakineticscroller.cpp
@@ -80,6 +80,7 @@ public:
     QAbstractScrollArea *area;
     QItemSelection oldSelection; // the selection before the first mouse down
     bool ignoreEvents;
+    bool isTouchEnabled;
     QPoint lastOvershoot; // don't change the type to QPointF or we might never shoot completely back.
     QPointer<QWidget> childWidget; // the widget where the mouse was pressed
     QPointF fractionalPosition;
@@ -94,6 +95,7 @@ public:
         : q_ptr(0)
         , area(0)
         , ignoreEvents(false)
+        , isTouchEnabled(false)
     {}
 
     void init()
@@ -164,6 +166,7 @@ void QScrollAreaKineticScroller::setWidget(QAbstractScrollArea *widget)
             view->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
             view->setHorizontalScrollMode(QAbstractItemView::ScrollPerPixel);
         }
+        d->isTouchEnabled = d->area->viewport()->testAttribute(Qt::WA_AcceptTouchEvents);
     }
 }
 
@@ -177,35 +180,87 @@ bool QScrollAreaKineticScroller::eventFilter(QObject *o, QEvent *e)
     bool isMouseDown = false;
 
     if (d->area && (o == d->area->viewport()) &&
-            !d->ignoreEvents && d->area->isEnabled() && isEnabled()) {
+        !d->ignoreEvents && d->area->isEnabled() && isEnabled()) {
         switch (e->type()) {
-            case QEvent::TouchBegin: {
-                QTouchEvent *te = static_cast<QTouchEvent *>(e);
-                if (te->touchPoints().count() == 1)
-                    res = handleInput(InputPress, te->touchPoints().at(0).pos() - d->lastOvershoot, timestamp);
+            case QEvent::TouchBegin:
+            case QEvent::TouchUpdate:
+            case QEvent::TouchEnd:
+                if (d->isTouchEnabled) {
+                    Input type = (e->type() == QEvent::TouchBegin) ? InputPress :
+                                ((e->type() == QEvent::TouchEnd) ? InputRelease : InputMove);
+                    QTouchEvent *te = static_cast<QTouchEvent *>(e);
+                    int idx = (te->deviceType() == QTouchEvent::TouchScreen) ? 0 : 1;
+
+                    if (te->touchPoints().count() == (idx + 1))
+                        res = handleInput(type, te->touchPoints().at(idx).pos() - d->lastOvershoot, timestamp);
+                }
                 break;
-            }
-            case QEvent::TouchUpdate: {
-                QTouchEvent *te = static_cast<QTouchEvent *>(e);
-                if (te->touchPoints().count() == 1)
-                    res = handleInput(InputMove, te->touchPoints().at(0).pos() - d->lastOvershoot, timestamp);
+
+            case QEvent::Wheel:
+#ifdef Q_WS_MAC
+                // the two-finger gesture is mapped to wheel events by default
+                res = d->isTouchEnabled;
+#endif
                 break;
-            }
-            case QEvent::TouchEnd: {
-                QTouchEvent *te = static_cast<QTouchEvent *>(e);
-                if (te->touchPoints().count() == 1)
-                    res = handleInput(InputRelease, te->touchPoints().at(0).pos() - d->lastOvershoot, timestamp);
+
+            case QEvent::MouseButtonPress:
+                if (!d->isTouchEnabled) {
+                    // re-install the event filter so that we get the mouse release before all other filters.
+                    // this is an evil hack, but hard to work around without prioritized event filters.
+                    d->area->viewport()->removeEventFilter(this);
+                    d->area->viewport()->installEventFilter(this);
+                }
+                // fall through
+
+            case QEvent::MouseButtonDblClick:
+                isMouseDown = true;
+                // fall through
+
+            case QEvent::MouseMove:
+            case QEvent::MouseButtonRelease:
+                if (!d->isTouchEnabled) {
+                    Input type = (e->type() == QEvent::MouseButtonRelease) ? InputRelease :
+                                ((e->type() == QEvent::MouseMove) ? InputMove : InputPress);
+                    QMouseEvent *me = static_cast<QMouseEvent *>(e);
+                    isMouseEvent = true;
+                    res = handleInput(type, me->posF() - d->lastOvershoot, timestamp);
+                }
+                break;
+
+            case QEvent::ChildAdded:
+            case QEvent::ChildRemoved: {
+                QChildEvent *ce = static_cast<QChildEvent *>(e);
+                if (ce->child()->isWidgetType()) {
+                    static_cast<QWidget *>(ce->child())->setAttribute(Qt::WA_TransparentForMouseEvents, ce->added());
+                    if ((e->type() == QEvent::ChildRemoved) && (ce->child() == d->childWidget))
+                        d->childWidget = 0;
+                }
                 break;
             }
             default:
                 break;
         }
     }
-    
+
     if (res)
         e->accept();
     res |= QObject::eventFilter(o, e);
 
+    // all child widgets get the WA_TransparentForMouseEvents attribute, so
+    // we have to find the "real" widget to forward this event to...
+    if (!res && isMouseEvent) {
+        QMouseEvent *me = static_cast<QMouseEvent *>(e);
+
+        if (isMouseDown)
+            d->childWidget = d->mouseTransparentChildAtGlobalPos(d->area->viewport(), me->globalPos());
+
+        if (d->childWidget) {
+            QMouseEvent cme(me->type(), me->pos(),
+                    me->globalPos(), me->button(), me->buttons(), me->modifiers());
+            d->sendEvent(d->childWidget, &cme);
+            res = cme.isAccepted();
+        }
+    }
     return res;
 }
 
@@ -250,21 +305,23 @@ void QScrollAreaKineticScroller::cancelPress(const QPointF &pressPos)
 
     QPoint pos = pressPos.toPoint();
 
-    /*
-    if (QWidget *childWidget = d->mouseTransparentChildAtGlobalPos(d->area->viewport(), d->view->mapToGlobal(pos))) {
-    */
     if (d->childWidget) {
-        // simulate a mouse-move and mouse-release far, far away
-        QPoint faraway(-1000, -1000);
-        QMouseEvent cmem(QEvent::MouseMove, faraway, d->childWidget->mapToGlobal(faraway),
-                Qt::LeftButton, QApplication::mouseButtons() | Qt::LeftButton,
-                QApplication::keyboardModifiers());
-        d->sendEvent(d->childWidget, &cmem);
-
-        QMouseEvent cmer(QEvent::MouseButtonRelease, faraway, d->childWidget->mapToGlobal(faraway),
-                Qt::LeftButton, QApplication::mouseButtons() & ~Qt::LeftButton,
-                QApplication::keyboardModifiers());
-        d->sendEvent(d->childWidget, &cmer);
+        if (d->isTouchEnabled) {
+            //TODO
+            // TouchUpdate + TouchEnd?
+        } else {
+            // simulate a mouse-move and mouse-release far, far away
+            QPoint faraway(-1000, -1000);
+            QMouseEvent cmem(QEvent::MouseMove, faraway, d->childWidget->mapToGlobal(faraway),
+                    Qt::LeftButton, QApplication::mouseButtons() | Qt::LeftButton,
+                    QApplication::keyboardModifiers());
+            d->sendEvent(d->childWidget, &cmem);
+
+            QMouseEvent cmer(QEvent::MouseButtonRelease, faraway, d->childWidget->mapToGlobal(faraway),
+                    Qt::LeftButton, QApplication::mouseButtons() & ~Qt::LeftButton,
+                    QApplication::keyboardModifiers());
+            d->sendEvent(d->childWidget, &cmer);
+        }
     }
 
     if (QAbstractItemView *view = qobject_cast<QAbstractItemView *>(d->area))