Updated the view to that of Tanja

umbra/view.py

@@ -49,13 +49,16 @@ class View:
             type (str): Role of file ('source' or 'shadow')
         """
         paths = filedialog.askopenfilenames(title="Select file",
-                                                 parent=self._window)
-                                                 # TODO: Which file type(s)?
+                                            parent=self._window,
+                                            filetypes=(('.csv files', '*.csv'),
+                                                       ("all files", "*.*")))
+        # TODO: Which file type(s)?
+
         # TODO: Deal with multiple files at once
         for path in paths:
             if path == "":  # Do not assign an empty file path
                 # TODO: Error message and close
-                select_files(type)
+                select_files(type) #prompt again
         return paths
 
     def update_files(self, paths, type):