[Events] Add toast hint to mark as done button.

app/src/main/java/pl/szczodrzynski/edziennik/ui/dialogs/event/EventDetailsDialog.kt

@@ -148,6 +148,10 @@ class EventDetailsDialog(
             openInCalendar()
         }
 
+        b.checkDoneButton.setOnLongClickListener {
+            Toast.makeText(activity, R.string.hint_mark_as_done, Toast.LENGTH_SHORT).show()
+            true
+        }
         b.goToTimetableButton.setOnLongClickListener {
             Toast.makeText(activity, R.string.hint_go_to_timetable, Toast.LENGTH_SHORT).show()
             true

app/src/main/res/values/strings.xml

@@ -1280,4 +1280,5 @@
     <string name="menu_add_remove_cards">Dodaj lub usuń karty</string>
     <string name="menu_template">Template</string>
     <string name="messages_attachment_download_again">Pobierz ponownie</string>
+    <string name="hint_mark_as_done">Oznacz jako wykonane</string>
 </resources>