Rely on the template loop for the ordering of the files

opentech/apply/stream_forms/fields.py

@@ -36,10 +36,10 @@ class MultiFileInput(ClearableFileInput):
             if not isinstance(upload, list):
                 upload = [upload]
 
-        checkbox_name = self.clear_checkbox_name(name)
+        checkbox_name = self.clear_checkbox_name(name) + '-'
         checkboxes = {k for k in data if checkbox_name in k}
         cleared = {
-            i for i, checkbox in enumerate(checkboxes)
+            int(checkbox.replace(checkbox_name, '')) for checkbox in checkboxes
             if CheckboxInput().value_from_datadict(data, files, checkbox)
         }
 

opentech/apply/stream_forms/templates/stream_forms/fields/multi_file_field.html

@@ -4,9 +4,13 @@
 </p>
 {% for file in widget.value %}
 <p>
-<input type="checkbox" name="{{ widget.checkbox_name }}-{{ forloop.counter }}" id="{{ widget.checkbox_id }}-{{ forloop.counter }}">
-<label for="{{ widget.checkbox_id }}-{{ forloop.counter }}"></label>
-<a href="{{ file.url }}">{{ file }}</a>
+    {% with y=forloop.counter0|stringformat:"s" %}
+    {% with file_id=widget.checkbox_name|add:'-'|add:y %}
+        <input type="checkbox" name="{{ file_id }}" id="{{ file_id }}">
+        <label for="{{ file_id }}"></label>
+    {% endwith %}
+    {% endwith %}
+    <a href="{{ file.url }}">{{ file }}</a>
 </p>
 {% endfor %}
 {{ widget.input_text }}{% endif %}