add ability to save current action sensitivities and restore them, and to disable all action sensitivity.

This is needed to be able to lock the application fully on OS X, where the global menu bar would still allow interaction
even when a modal dialog is displayed.

gtk2_ardour/ardour.menus.in

@@ -56,6 +56,8 @@
       <menuitem action='toggle-about'/>
       <menuitem action='toggle-rc-options-editor'/>
 #endif
+      <separator/>
+      <menuitem action='lock'/>
 #ifndef GTKOSX
       <separator/>
       <menuitem action='Quit'/>

gtk2_ardour/editor.h

@@ -452,6 +452,7 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	}
 
  	ArdourCanvas::Container* get_trackview_group () const { return _trackview_group; }
+        ArdourCanvas::Container* get_noscroll_group () const { return no_scroll_group; }
         ArdourCanvas::ScrollGroup* get_hscroll_group () const { return h_scroll_group; }
         ArdourCanvas::ScrollGroup* get_vscroll_group () const { return v_scroll_group; }
         ArdourCanvas::ScrollGroup* get_hvscroll_group () const { return hv_scroll_group; }
@@ -758,6 +759,9 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	*/
         ArdourCanvas::ScrollGroup* h_scroll_group;
 
+	/* The group containing all trackviews. */
+	ArdourCanvas::Container* no_scroll_group;
+
 	/* The group containing all trackviews. */
 	ArdourCanvas::Container* _trackview_group;
 
@@ -1352,6 +1356,8 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	DragManager* _drags;
 
 	void escape ();
+	void lock ();
+	void unlock ();
 
 	Gtk::Menu fade_context_menu;
 

gtk2_ardour/editor_actions.cc

@@ -150,6 +150,11 @@ Editor::register_actions ()
 
 	ActionManager::register_action (editor_actions, "escape", _("Break drag or deselect all"), sigc::mem_fun (*this, &Editor::escape));
 
+	/* We don't bother registering "unlock" because it would be insensitive
+	   when required. Editor::unlock() must be invoked directly.
+	*/
+	ActionManager::register_action (editor_actions, "lock", _("Lock"), sigc::mem_fun (*this, &Editor::lock));
+
 	toggle_reg_sens (editor_actions, "show-editor-mixer", _("Show Editor Mixer"), sigc::mem_fun (*this, &Editor::editor_mixer_button_toggled));
 	toggle_reg_sens (editor_actions, "show-editor-list", _("Show Editor List"), sigc::mem_fun (*this, &Editor::editor_list_button_toggled));
 

gtk2_ardour/editor_canvas.cc

@@ -68,6 +68,11 @@ Editor::initialize_canvas ()
 	_track_canvas_viewport = new ArdourCanvas::GtkCanvasViewport (horizontal_adjustment, vertical_adjustment);
 	_track_canvas = _track_canvas_viewport->canvas ();
 
+	/* scroll group for items that should not automatically scroll
+	 *  (e.g verbose cursor). It shares the canvas coordinate space.
+	*/
+	no_scroll_group = new ArdourCanvas::Container (_track_canvas->root());
+
 	ArdourCanvas::ScrollGroup* hsg; 
 	ArdourCanvas::ScrollGroup* hg;
 	ArdourCanvas::ScrollGroup* vg;

gtk2_ardour/editor_ops.cc

@@ -57,6 +57,7 @@
 
 #include "canvas/canvas.h"
 
+#include "actions.h"
 #include "ardour_ui.h"
 #include "audio_region_view.h"
 #include "audio_streamview.h"
@@ -7116,3 +7117,15 @@ Editor::toggle_midi_input_active (bool flip_others)
 	
 	_session->set_exclusive_input_active (rl, onoff, flip_others);
 }
+
+void
+Editor::lock ()
+{
+	ActionManager::disable_all_actions ();
+}
+
+void
+Editor::unlock ()
+{
+	ActionManager::pop_action_state ();
+}

gtk2_ardour/verbose_cursor.cc

@@ -44,7 +44,7 @@ VerboseCursor::VerboseCursor (Editor* editor)
 	, _xoffset (0)
 	, _yoffset (0)
 {
-	_canvas_item = new ArdourCanvas::Text (_editor->get_hvscroll_group());
+	_canvas_item = new ArdourCanvas::Text (_editor->get_noscroll_group());
 	CANVAS_DEBUG_NAME (_canvas_item, "verbose canvas cursor");
 	_canvas_item->set_ignore_events (true);
 	_canvas_item->set_font_description (Pango::FontDescription (ARDOUR_UI::config()->get_canvasvar_LargerBoldFont()));

libs/gtkmm2ext/actions.cc

@@ -21,8 +21,11 @@
 #include <vector>
 #include <string>
 #include <list>
+#include <stack>
 #include <stdint.h>
 
+#include <boost/shared_ptr.hpp>
+
 #include <gtk/gtkaccelmap.h>
 #include <gtk/gtkuimanager.h>
 #include <gtk/gtkactiongroup.h>
@@ -232,6 +235,81 @@ ActionManager::get_all_actions (vector<string>& names, vector<string>& paths, ve
 	}
 }
 
+struct ActionState {
+	GtkAction* action;
+	bool       sensitive;
+	ActionState (GtkAction* a, bool s) : action (a), sensitive (s) {}
+};
+
+typedef std::vector<ActionState> ActionStates;
+
+static std::stack<boost::shared_ptr<ActionStates> > state_stack;
+
+static boost::shared_ptr<ActionStates>
+get_action_state ()
+{
+	boost::shared_ptr<ActionStates> state = boost::shared_ptr<ActionStates>(new ActionStates);
+	
+	/* the C++ API for functions used here appears to be broken in
+	   gtkmm2.6, so we fall back to the C level.
+	*/
+
+	GList* list = gtk_ui_manager_get_action_groups (ActionManager::ui_manager->gobj());
+	GList* node;
+	GList* acts;
+
+	for (node = list; node; node = g_list_next (node)) {
+
+		GtkActionGroup* group = (GtkActionGroup*) node->data;
+
+		/* first pass: collect them all */
+
+		typedef std::list<Glib::RefPtr<Gtk::Action> > action_list;
+		action_list the_acts;
+
+		for (acts = gtk_action_group_list_actions (group); acts; acts = g_list_next (acts)) {
+			GtkAction* action = (GtkAction*) acts->data;
+
+			state->push_back (ActionState (action, gtk_action_get_sensitive (action)));
+		}
+	}
+	
+	return state;
+}
+
+void
+ActionManager::push_action_state ()
+{
+	state_stack.push (get_action_state());
+}
+
+void
+ActionManager::pop_action_state ()
+{
+	if (state_stack.empty()) {
+		warning << string_compose (_("programming error: %1"), X_("ActionManager::pop_action_state called with empty stack")) << endmsg;
+		return;
+	}
+
+	boost::shared_ptr<ActionStates> as = state_stack.top ();
+	state_stack.pop ();
+	
+	for (ActionStates::iterator i = as->begin(); i != as->end(); ++i) {
+		gtk_action_set_sensitive ((*i).action, (*i).sensitive);
+	}
+}
+
+void
+ActionManager::disable_all_actions ()
+{
+	push_action_state ();
+	boost::shared_ptr<ActionStates> as = state_stack.top ();
+	
+	for (ActionStates::iterator i = as->begin(); i != as->end(); ++i) {
+		gtk_action_set_sensitive ((*i).action, false);
+	}
+}
+
 void
 ActionManager::add_action_group (RefPtr<ActionGroup> grp)
 {

libs/gtkmm2ext/gtkmm2ext/actions.h

@@ -91,6 +91,11 @@ namespace ActionManager {
 	LIBGTKMM2EXT_API extern void check_toggleaction (std::string);
 	LIBGTKMM2EXT_API extern void uncheck_toggleaction (std::string);
 	LIBGTKMM2EXT_API extern void set_toggleaction_state (std::string, bool);
+
+       
+        LIBGTKMM2EXT_API extern void push_action_state ();
+        LIBGTKMM2EXT_API extern void pop_action_state ();
+        LIBGTKMM2EXT_API extern void disable_all_actions ();
 };
 
 #endif /* __libgtkmm2ext_actions_h__ */