Fix Adding "ToDo" note crash when no active object (#685)

* Fix Adding "ToDo" note crash when no active object

Fixes #10795

* Better message when no active object.

* resolve conflict: Fixes #10795

gramps/plugins/gramplet/todo.py

@@ -32,6 +32,7 @@ from gi.repository import Gtk
 from gramps.gen.plug import Gramplet
 from gramps.gui.widgets.styledtexteditor import StyledTextEditor
 from gramps.gui.widgets import SimpleButton
+from gramps.gui.dialog import WarningDialog
 from gramps.gen.lib import StyledText, Note, NoteType
 from gramps.gen.db import DbTxn
 from gramps.gen.errors import WindowActiveError
@@ -185,6 +186,9 @@ class ToDo(Gramplet):
         """
         Create a new To Do note.
         """
+        nav_type = self.uistate.viewmanager.active_page.navigation_type()
+        active_handle = self.get_active(nav_type)
+        if active_handle:
             from gramps.gui.editors import EditNote
             note = Note()
             note.set_type(NoteType.TODO)
@@ -192,6 +196,11 @@ class ToDo(Gramplet):
                 EditNote(self.gui.dbstate, self.gui.uistate, [], note, self.created)
             except WindowActiveError:
                 pass
+        else:
+            WarningDialog(_("No active object"),
+                _("First select the object to which you want to attach a note")
+                    + _(":") + _(nav_type),
+                parent=self.uistate.window)
 
 class PersonToDo(ToDo):
     """