Documentation

[quassel.git] / src / qtui / chatview.cpp

diff --git a/src/qtui/chatview.cpp b/src/qtui/chatview.cpp
index 5e76a33..c6e6209 100644 (file)
--- a/src/qtui/chatview.cpp
+++ b/src/qtui/chatview.cpp
@@ -110,9 +110,12 @@ bool ChatView::event(QEvent *event)
     }
 
     if (event->type() == QEvent::TouchBegin) {
+        // Enable scrolling by draging, disable selecting/clicking content
         setDragMode(QGraphicsView::ScrollHandDrag);
         setInteractive(false);
-        if (verticalScrollBar()->isVisible()) return true; //if scrollbar is not visible we need to request backlog below
+        // if scrollbar is not visible we need to request backlog below else we need to accept 
+        // the event now (return true) so that we will receive TouchUpdate and TouchEnd/TouchCancel
+        if (verticalScrollBar()->isVisible()) return true;
     }
 
 #if QT_VERSION >= 0x050000
@@ -120,24 +123,28 @@ bool ChatView::event(QEvent *event)
 #else
     if (event->type() == QEvent::TouchEnd) {
 #endif
+        // End scroll and reset settings to default
         setDragMode(QGraphicsView::NoDrag);
         setInteractive(true);
-               _firstTouchUpdateHappened = false;
+        _firstTouchUpdateHappened = false;
         return true;
     }
 
-       if (event->type() == QEvent::TouchUpdate) {
-               if (!_firstTouchUpdateHappened) {
-                       QTouchEvent::TouchPoint p = ((QTouchEvent*)event)->touchPoints().at(0);
-                       double dx = abs (p.lastPos().x() - p.pos().x());
-                       double dy = abs (p.lastPos().y() - p.pos().y());
-                       if (dx > dy) {
-                               setDragMode(QGraphicsView::NoDrag);
-                               setInteractive(true);
-                       }
-                       _firstTouchUpdateHappened = true;
-               }
-       }
+    if (event->type() == QEvent::TouchUpdate) {
+        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.
+            QTouchEvent::TouchPoint p = ((QTouchEvent*)event)->touchPoints().at(0);
+            double dx = abs (p.lastPos().x() - p.pos().x());
+            double dy = abs (p.lastPos().y() - p.pos().y());
+            if (dx > dy) {
+                setDragMode(QGraphicsView::NoDrag);
+                setInteractive(true);
+            }
+            _firstTouchUpdateHappened = true;
+        }
+        // Applying the movement happens automatically by the drag-mode
+    }
 
     if (event->type() == QEvent::Wheel || event->type() == QEvent::TouchBegin || event->type() == QEvent::TouchUpdate) {
         if (!verticalScrollBar()->isVisible()) {