Improved drag selection logic

[pulseview.git] / pv / view / header.cpp

diff --git a/pv/view/header.cpp b/pv/view/header.cpp
index 8434e2c8dc9ffb289c676f338d151793367e5a8e..e50d851f686d315bc584f5e92510218b85f3ad08 100644 (file)
--- a/pv/view/header.cpp
+++ b/pv/view/header.cpp
@@ -114,23 +114,77 @@ void Header::mousePressEvent(QMouseEvent *event)
        if(~QApplication::keyboardModifiers() & Qt::ControlModifier) {
                // Unselect all other signals because the Ctrl is not
                // pressed
+               _drag_sigs.clear();
                BOOST_FOREACH(const shared_ptr<Signal> s, sigs)
                        s->select(false);
        }
 
+       if(event->button() & Qt::LeftButton) {
+               _mouse_down_point = event->pos();
+
+               // Save the offsets of any signals which will be dragged
+               BOOST_FOREACH(const shared_ptr<Signal> s, sigs)
+                       if(s->selected())
+                               _drag_sigs.push_back(
+                                       make_pair(s, s->get_v_offset()));
+       }
+
        // Select the signal if it has been clicked
        const shared_ptr<Signal> mouse_over_signal =
                get_mouse_over_signal(event->pos());
-       if(mouse_over_signal)
-               mouse_over_signal->select(!mouse_over_signal->selected());
+       if(mouse_over_signal) {
+               if(mouse_over_signal->selected())
+                       mouse_over_signal->select(false);
+               else {
+                       mouse_over_signal->select(true);
+
+                       // Add the signal to the drag list
+                       _drag_sigs.push_back(
+                               make_pair(mouse_over_signal,
+                                       mouse_over_signal->get_v_offset()));
+               }
+       }
 
        update();
 }
 
+void Header::mouseReleaseEvent(QMouseEvent *event)
+{
+       assert(event);
+       if(event->button() == Qt::LeftButton)
+               _drag_sigs.clear();
+}
+
 void Header::mouseMoveEvent(QMouseEvent *event)
 {
        assert(event);
        _mouse_point = event->pos();
+
+       // Move the signals if we are dragging
+       if(!_drag_sigs.empty()) {
+               const int delta = event->pos().y() - _mouse_down_point.y();
+
+               for(std::list<std::pair<boost::weak_ptr<Signal>,
+                       int> >::iterator i = _drag_sigs.begin();
+                       i != _drag_sigs.end(); i++) {
+                       const boost::shared_ptr<Signal> sig((*i).first);
+                       if(sig) {
+                               const int y = (*i).second + delta;
+                               const int y_snap =
+                                       ((y + View::SignalSnapGridSize / 2) /
+                                               View::SignalSnapGridSize) *
+                                               View::SignalSnapGridSize;
+                               sig->set_v_offset(y_snap);
+
+                               // Ensure the signal is selected
+                               sig->select();
+                       }
+                       
+               }
+
+               signals_moved();
+       }
+
        update();
 }