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[quassel.git] / src / uisupport / treeviewtouch.cpp

diff --git a/src/uisupport/treeviewtouch.cpp b/src/uisupport/treeviewtouch.cpp
index adfb917..13db59d 100644 (file)
--- a/src/uisupport/treeviewtouch.cpp
+++ b/src/uisupport/treeviewtouch.cpp
@@ -24,44 +24,57 @@
 #include <QScrollBar>
 
 TreeViewTouch::TreeViewTouch(QWidget *parent)
-       : QTreeView(parent)
+    : QTreeView(parent)
 {
-       setAttribute(Qt::WA_AcceptTouchEvents);
+    setAttribute(Qt::WA_AcceptTouchEvents);
 }
 
-
 bool TreeViewTouch::event(QEvent *event) {
-       if (event->type() == QEvent::TouchBegin && _lastTouchStart < QDateTime::currentMSecsSinceEpoch() - 1000) { //(slow) double tab = normal behaviour = select multiple. 1000 ok?
-               _touchScrollInProgress = true;
-               _lastTouchStart = QDateTime::currentMSecsSinceEpoch();
-               setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
-               return true;
-       }
+    if (event->type() == QEvent::TouchBegin) {
+        // Register that we may be scrolling, set the scroll mode to scroll-per-pixel
+        // and accept the event (return true) so that we will receive TouchUpdate and TouchEnd/TouchCancel
+        _touchScrollInProgress = true;
+        setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
+        return true;
+    }
 
-       if (event->type() == QEvent::TouchUpdate && _touchScrollInProgress) {
-               QTouchEvent::TouchPoint p = ((QTouchEvent*)event)->touchPoints().at(0);
-               verticalScrollBar()->setValue(verticalScrollBar()->value() - (p.pos().y() - p.lastPos().y()));
-               return true;
-       }
+    if (event->type() == QEvent::TouchUpdate && _touchScrollInProgress) {
+        QTouchEvent::TouchPoint p = ((QTouchEvent*)event)->touchPoints().at(0);
+        if (!_firstTouchUpdateHappened) {
+            // After the first movement of a Touch-Point, calculate the distance in both axis
+            // and if the point moved more horizontally abort scroll.
+            double dx = abs(p.lastPos().x() - p.pos().x());
+            double dy = abs(p.lastPos().y() - p.pos().y());
+            if (dx > dy) {
+                _touchScrollInProgress = false;
+            }
+            _firstTouchUpdateHappened = true;
+        }
+        // Apply touch movement to scrollbar
+        verticalScrollBar()->setValue(verticalScrollBar()->value() - (p.pos().y() - p.lastPos().y()));
+        return true;
+    }
 
 #if QT_VERSION >= 0x050000
-       if (event->type() == QEvent::TouchEnd || event->type() == QEvent::TouchCancel) {
+    if (event->type() == QEvent::TouchEnd || event->type() == QEvent::TouchCancel) {
 #else
     if (event->type() == QEvent::TouchEnd) {
 #endif
-               _touchScrollInProgress = false;
-               return true;
-       }
+        // End scroll and reset variables
+        _touchScrollInProgress = false;
+        _firstTouchUpdateHappened = false;
+        return true;
+    }
 
-       return QTreeView::event(event);
+    return QTreeView::event(event);
 }
 
 void TreeViewTouch::mousePressEvent(QMouseEvent * event) {
-       if (!_touchScrollInProgress)
-               QTreeView::mousePressEvent(event);
+    if (!_touchScrollInProgress)
+        QTreeView::mousePressEvent(event);
 }
 
 void TreeViewTouch::mouseMoveEvent(QMouseEvent * event) {
-       if (!_touchScrollInProgress)
-               QTreeView::mouseMoveEvent(event);
+    if (!_touchScrollInProgress)
+        QTreeView::mouseMoveEvent(event);
 };