[BirthdaysGramplet]Add 'Only show birthdays with tag' functionality[gramps51](#213)

As requested by @wroldwiedbwe an opposite option that only shows birthdays of persons tagged with a certain tag:

All birthdays are shown when neither the 'ignore tag' nor the 'only tag' is selected. The 'ignore tag' hides all birthdays of people tagged with it and the 'only tag' hides all birthdays of person NOT tagged with it. If a person is tagged with both tags (ignore and only) the birthday will be ignored. The tag names don't have to be 'ignore' or 'only'. All tag names are valid.

Author: Mattkmmr

BirthdaysGramplet/BirthdaysGramplet.py

@@ -42,34 +42,42 @@ def build_options(self):
         """Build the configuration options"""
         db = self.dbstate.db
 
-        name = _("Ignore birthdays with tag")
-        self.option = EnumeratedListOption(name, self.ignore_tag)
+        name_ignore = _("Ignore birthdays with tag")
+        name_only = _("Only show birthdays with tag")
+        self.opt_ignore = EnumeratedListOption(name_ignore, self.ignore_tag)
+        self.opt_only = EnumeratedListOption(name_only, self.only_tag)
 
-        self.option.add_item('', '')  # No ignore tag
+        self.opt_ignore.add_item('', '')  # No ignore tag
+        self.opt_only.add_item('', '')
         if db.is_open():
             for tag_handle in db.get_tag_handles(sort_handles=True):
                 tag = db.get_tag_from_handle(tag_handle)
                 tag_name = tag.get_name()
-                self.option.add_item(tag_name, tag_name)
+                self.opt_ignore.add_item(tag_name, tag_name)
+                self.opt_only.add_item(tag_name, tag_name)
 
-        self.add_option(self.option)
+        self.add_option(self.opt_ignore)
+        self.add_option(self.opt_only)
 
     def save_options(self):
         """Save gramplet configuration data"""
-        self.ignore_tag = self.option.get_value()
+        self.ignore_tag = self.opt_ignore.get_value()
+        self.only_tag = self.opt_only.get_value()
 
     def save_update_options(self, obj):
         """Save a gramplet's options to file"""
         self.save_options()
-        self.gui.data = [self.ignore_tag]
+        self.gui.data = [self.ignore_tag, self.only_tag]
         self.update()
 
     def on_load(self):
         """Load stored configuration data"""
-        if len(self.gui.data) == 1:
+        if len(self.gui.data) == 2:
             self.ignore_tag = self.gui.data[0]
+            self.only_tag = self.gui.data[1]
         else:
             self.ignore_tag = ''
+            self.only_tag = ''
 
     def db_changed(self):
         """Update gramplet when database was changed"""
@@ -81,24 +89,29 @@ def main(self):
         """Main function of the Birthdays gramplet"""
         self.set_text(_("Processing..."))
         database = self.dbstate.db
-        personList = database.iter_people()
+        person_list = database.iter_people()
         self.result = []
 
-        # get ignore tag handle
-        ignore_tag_handle = ""  # No ignore handle selceted by user
-        tag_name = self.option.get_value()
+        ignore_tag_handle = ""
+        only_tag_handle = ""
+        tag_name_ignore = self.opt_ignore.get_value()
+        tag_name_only = self.opt_only.get_value()
         tag_handles = database.get_tag_handles()
         for handle in tag_handles:
             tag = database.get_tag_from_handle(handle)
-            if tag_name == tag.get_name():
-                # overwrite ignore_handle to user selction
+            # overwrite ignore_handle and only_handle to user selection
+            # if a handle is selected
+            if tag_name_ignore == tag.get_name():
                 ignore_tag_handle = tag.get_handle()
+            if tag_name_only == tag.get_name():
+                only_tag_handle = tag.get_handle()
 
-        for cnt, person in enumerate(personList):
-            person_tag_handles = person.get_tag_list()
-            if ignore_tag_handle in person_tag_handles:
+        for person in list(person_list):
+            pers_tag_handles = person.get_tag_list()
+            if ignore_tag_handle in pers_tag_handles:
                 pass  # ignore person
-            else:  # calculate age and days until birthday:
+            elif only_tag_handle in pers_tag_handles or only_tag_handle == "":
+                # calculate age and days until birthday
                 self.__calculate(database, person)
 
         # Reverse sort on number of days from now: