Grab keyboard only with note selection.

When entered, the keyboard is grabbed when the selection becomes non-empty, and
ungrabbed if it becomes empty again or the region is left or the user switches
out of internal mode.

This fixes scroll in internal mode and note moving with arrow keys.  Also frees
up useful keybindings when there is no note selection, which is much nicer than
the "nothing works in edit mode at all" greedy grab approach used previously.

Attempt #874327892 of getting this damned grabbing right.

1 files changed, 68 insertions, 19 deletions

diff --git a/gtk2_ardour/midi_region_view.cc b/gtk2_ardour/midi_region_view.cc
index bad479bc26..affe77585b 100644
--- a/gtk2_ardour/midi_region_view.cc
+++ b/gtk2_ardour/midi_region_view.cc
@@ -119,6 +119,8 @@ MidiRegionView::MidiRegionView (ArdourCanvas::Container*      parent,
 	, _no_sound_notes (false)
 	, _last_event_x (0)
 	, _last_event_y (0)
+	, _grabbed_keyboard (false)
+	, _entered (false)
 	, pre_enter_cursor (0)
 	, pre_press_cursor (0)
 	, pre_note_enter_cursor (0)
@@ -162,6 +164,8 @@ MidiRegionView::MidiRegionView (ArdourCanvas::Container*      parent,
 	, _no_sound_notes (false)
 	, _last_event_x (0)
 	, _last_event_y (0)
+	, _grabbed_keyboard (false)
+	, _entered (false)
 	, pre_enter_cursor (0)
 	, pre_press_cursor (0)
 	, pre_note_enter_cursor (0)
@@ -211,6 +215,8 @@ MidiRegionView::MidiRegionView (const MidiRegionView& other)
 	, _no_sound_notes (false)
 	, _last_event_x (0)
 	, _last_event_y (0)
+	, _grabbed_keyboard (false)
+	, _entered (false)
 	, pre_enter_cursor (0)
 	, pre_press_cursor (0)
 	, pre_note_enter_cursor (0)
@@ -242,6 +248,8 @@ MidiRegionView::MidiRegionView (const MidiRegionView& other, boost::shared_ptr<M
 	, _no_sound_notes (false)
 	, _last_event_x (0)
 	, _last_event_y (0)
+	, _grabbed_keyboard (false)
+	, _entered (false)
 	, pre_enter_cursor (0)
 	, pre_press_cursor (0)
 	, pre_note_enter_cursor (0)
@@ -406,10 +414,9 @@ MidiRegionView::enter_notify (GdkEventCrossing* ev)
 		_mouse_mode_connection, invalidator (*this), boost::bind (&MidiRegionView::mouse_mode_changed, this), gui_context ()
 		);
 
-	if (trackview.editor().current_mouse_mode() == MouseDraw && _mouse_state != AddDragging) {
-		create_ghost_note (ev->x, ev->y);
-	}
+	enter_internal();
 
+	_entered = true;
 	return false;
 }
 
@@ -418,27 +425,48 @@ MidiRegionView::leave_notify (GdkEventCrossing*)
 {
 	_mouse_mode_connection.disconnect ();
 
-	trackview.editor().verbose_cursor()->hide ();
-	remove_ghost_note ();
+	leave_internal();
 
+	_entered = false;
 	return false;
 }
 
 void
 MidiRegionView::mouse_mode_changed ()
 {
-	if (trackview.editor().current_mouse_mode() == MouseDraw && trackview.editor().internal_editing()) {
-		create_ghost_note (_last_event_x, _last_event_y);
+	if (trackview.editor().internal_editing()) {
+		// Switched in to internal editing mode while entered
+		enter_internal();
 	} else {
-		remove_ghost_note ();
-		trackview.editor().verbose_cursor()->hide ();
+		// Switched out of internal editing mode while entered
+		leave_internal();
 	}
+}
 
-	if (!trackview.editor().internal_editing()) {
-		Keyboard::magic_widget_drop_focus();
-	} else {
+void
+MidiRegionView::enter_internal()
+{
+	if (trackview.editor().current_mouse_mode() == MouseDraw && _mouse_state != AddDragging) {
+		// Show ghost note under pencil
+		create_ghost_note(_last_event_x, _last_event_y);
+	}
+
+	if (!_selection.empty()) {
+		// Grab keyboard for moving selected notes with arrow keys
 		Keyboard::magic_widget_grab_focus();
-		group->grab_focus();
+		_grabbed_keyboard = true;
+	}
+}
+
+void
+MidiRegionView::leave_internal()
+{
+	trackview.editor().verbose_cursor()->hide ();
+	remove_ghost_note ();
+
+	if (_grabbed_keyboard) {
+		Keyboard::magic_widget_drop_focus();
+		_grabbed_keyboard = false;
 	}
 }
 
@@ -2052,6 +2080,12 @@ MidiRegionView::clear_selection_except (NoteBase* ev, bool signal)
 		}
 	}
 
+	if (!ev && _entered) {
+		// Clearing selection entirely, ungrab keyboard
+		Keyboard::magic_widget_drop_focus();
+		_grabbed_keyboard = false;
+	}
+
 	/* this does not change the status of this regionview w.r.t the editor
 	   selection.
 	*/
@@ -2064,6 +2098,8 @@ MidiRegionView::clear_selection_except (NoteBase* ev, bool signal)
 void
 MidiRegionView::unique_select(NoteBase* ev)
 {
+	const bool selection_was_empty = _selection.empty();
+
 	clear_selection_except (ev);
 
 	/* don't bother with checking to see if we should remove this
@@ -2074,6 +2110,11 @@ MidiRegionView::unique_select(NoteBase* ev)
 
 	if (!ev->selected()) {
 		add_to_selection (ev);
+		if (selection_was_empty && _entered) {
+			// Grab keyboard for moving notes with arrow keys
+			Keyboard::magic_widget_grab_focus();
+			_grabbed_keyboard = true;
+		}
 	}
 }
 
@@ -2345,6 +2386,11 @@ MidiRegionView::remove_from_selection (NoteBase* ev)
 
 	if (i != _selection.end()) {
 		_selection.erase (i);
+		if (_selection.empty() && _grabbed_keyboard) {
+			// Ungrab keyboard
+			Keyboard::magic_widget_drop_focus();
+			_grabbed_keyboard = false;
+		}
 	}
 
 	ev->set_selected (false);
@@ -2359,18 +2405,19 @@ MidiRegionView::remove_from_selection (NoteBase* ev)
 void
 MidiRegionView::add_to_selection (NoteBase* ev)
 {
-	bool add_mrv_selection = false;
-
-	if (_selection.empty()) {
-		add_mrv_selection = true;
-	}
+	const bool selection_was_empty = _selection.empty();
 
 	if (_selection.insert (ev).second) {
 		ev->set_selected (true);
 		start_playing_midi_note ((ev)->note());
+		if (selection_was_empty && _entered) {
+			// Grab keyboard for moving notes with arrow keys
+			Keyboard::magic_widget_grab_focus();
+			_grabbed_keyboard = true;
+		}
 	}
 
-	if (add_mrv_selection) {
+	if (selection_was_empty) {
 		PublicEditor& editor (trackview.editor());
 		editor.get_selection().add (this);
 	}
@@ -3600,6 +3647,8 @@ MidiRegionView::drop_down_keys ()
 void
 MidiRegionView::maybe_select_by_position (GdkEventButton* ev, double /*x*/, double y)
 {
+	/* XXX: This is dead code.  What was it for? */
+
 	double note = midi_stream_view()->y_to_note(y);
 	Events e;
 	MidiTimeAxisView* const mtv = dynamic_cast<MidiTimeAxisView*>(&trackview);