TraceView: Restore vertical offset

diff --git a/pv/view/view.cpp b/pv/view/view.cpp
index 39a8ef4b07019141d64b61924d1c6da94a930237..6549e51bf85041a225b215c2268989461f7ceae1 100644 (file)
--- a/pv/view/view.cpp
+++ b/pv/view/view.cpp
@@ -155,7 +155,8 @@ View::View(Session &session, QWidget *parent) :
        next_flag_text_('A'),
        trigger_markers_(),
        hover_point_(-1, -1),
-       scroll_needs_defaults(false)
+       scroll_needs_defaults(false),
+       saved_v_offset_(0)
 {
        connect(scrollarea_.horizontalScrollBar(), SIGNAL(valueChanged(int)),
                this, SLOT(h_scroll_value_changed(int)));
@@ -280,6 +281,8 @@ const Viewport* View::viewport() const
 void View::save_settings(QSettings &settings) const
 {
        settings.setValue("scale", scale_);
+       settings.setValue("v_offset",
+               scrollarea_.verticalScrollBar()->sliderPosition());
 
        std::stringstream ss;
        boost::archive::text_oarchive oa(ss);
@@ -295,6 +298,9 @@ void View::save_settings(QSettings &settings) const
 
 void View::restore_settings(QSettings &settings)
 {
+       // Note: It is assumed that this function is only called once,
+       // immediately after restoring a previous session.
+
        if (settings.contains("scale"))
                set_scale(settings.value("scale").toDouble());
 
@@ -314,6 +320,13 @@ void View::restore_settings(QSettings &settings)
                signal->restore_settings(settings);
                settings.endGroup();
        }
+
+       if (settings.contains("v_offset")) {
+               saved_v_offset_ = settings.value("v_offset").toInt();
+               set_v_offset(saved_v_offset_);
+               scroll_needs_defaults = false;
+               // Note: see resizeEvent() for additional information
+       }
 }
 
 vector< shared_ptr<TimeItem> > View::time_items() const
@@ -956,6 +969,20 @@ bool View::eventFilter(QObject *object, QEvent *event)
 void View::resizeEvent(QResizeEvent*)
 {
        update_layout();
+
+       // This is somewhat of a hack, unfortunately. We cannot use
+       // set_v_offset() from within restore_settings() as the view
+       // at that point is neither visible nor properly sized.
+       // This is the least intrusive workaround I could come up
+       // with: set the vertical offset when the view is visible and
+       // resized to its final size. Resize events that are sent
+       // when the view is invisible must be ignored as they have
+       // wrong sizes, potentially preventing the v offset to be
+       // set successfully.
+       if (isVisible() && saved_v_offset_) {
+               set_v_offset(saved_v_offset_);
+               saved_v_offset_ = 0;
+       }
 }
 
 void View::row_item_appearance_changed(bool label, bool content)

diff --git a/pv/view/view.hpp b/pv/view/view.hpp
index 2f5d7020f05011c70594589ca95c4d50bae2bb65..379c243507dff5b33c4d748a2074031988e190bc 100644 (file)
--- a/pv/view/view.hpp
+++ b/pv/view/view.hpp
@@ -424,6 +424,9 @@ private:
 
        // This is true when the defaults couldn't be set due to insufficient info
        bool scroll_needs_defaults;
+
+       // A nonzero value indicates the v offset to restore. See View::resizeEvent()
+       int saved_v_offset_;
 };
 
 } // namespace TraceView