add ownership overview in list view

jdav_web/material/admin.py

@@ -42,7 +42,8 @@ class NotTooOldFilter(SimpleListFilter):
 class MaterialAdmin(admin.ModelAdmin):
     """Edit view of a MaterialPart"""
 
-    list_display = ('name', 'description', 'quantity_real', 'buy_date',
+    list_display = ('name', 'description', 'quantity_real',
+                    'ownership_overview', 'buy_date',
                     'lifetime', 'not_too_old', 'admin_thumbnail')
     inlines = [OwnershipInline]
     list_filter = (NotTooOldFilter,)

jdav_web/material/locale/de/LC_MESSAGES/django.po

@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2017-07-05 18:57+0200\n"
+"POT-Creation-Date: 2017-07-05 19:07+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -66,30 +66,34 @@ msgstr "Anzahl"
 msgid "Thumbnail"
 msgstr "Bild"
 
-#: models.py:51
+#: models.py:49
+msgid "Owners"
+msgstr "Verantwortliche"
+
+#: models.py:59
 msgid "Not too old?"
 msgstr "Nicht zu alt?"
 
-#: models.py:54
+#: models.py:62
 msgid "material part"
 msgstr "Materialteil"
 
-#: models.py:55
+#: models.py:63
 msgid "material parts"
 msgstr "Materialteile"
 
-#: models.py:61
+#: models.py:69
 msgid "owner"
 msgstr "Besitzer"
 
-#: models.py:62
+#: models.py:70
 msgid "count"
 msgstr "Anzahl"
 
-#: models.py:69
+#: models.py:77
 msgid "ownership"
 msgstr "Besitzer"
 
-#: models.py:70
+#: models.py:78
 msgid "ownerships"
 msgstr "Verantwortliche"

jdav_web/material/models.py

@@ -40,6 +40,14 @@ class MaterialPart(models.Model):
     admin_thumbnail.short_description = _('Thumbnail')
     admin_thumbnail.allow_tags = True
 
+    def ownership_overview(self):
+        summary = ''
+        for owner in self.ownership_set.all():
+            summary += '<p>{}: {}</p>'.format(str(owner.owner), owner.count)
+        return summary
+    ownership_overview.allow_tags = True
+    ownership_overview.short_description = _('Owners')
+
     def not_too_old(self):
         """Returns wether the part should be replaced cause of age"""
         buy_time = timezone.make_aware(datetime.combine(self.buy_date,