Refactor PartAttachmentWidget

- Now displays generic attachments
- Augment the InvenTreeAttachment class to "know" about its model reference

lib/inventree/model.dart

@@ -636,6 +636,9 @@ class InvenTreeAttachment extends InvenTreeModel {
 
   InvenTreeAttachment.fromJson(Map<String, dynamic> json) : super.fromJson(json);
 
+  // Override this reference field for any subclasses
+  String get REFERENCE_FIELD => "";
+
   String get attachment => (jsondata["attachment"] ?? "") as String;
 
   // Return the filename of the attachment
@@ -684,19 +687,27 @@ class InvenTreeAttachment extends InvenTreeModel {
     }
   }
 
-  Future<bool> uploadAttachment(File attachment, {String comment = "", Map<String, String> fields = const {}}) async {
+  Future<bool> uploadAttachment(File attachment, int parentId, {String comment = "", Map<String, String> fields = const {}}) async {
+
+    // Ensure that the correct reference field is set
+    Map<String, String> data = Map<String, String>.from(fields);
+
+    data[REFERENCE_FIELD] = parentId.toString();
 
     final APIResponse response = await InvenTreeAPI().uploadFile(
         URL,
         attachment,
         method: "POST",
         name: "attachment",
-        fields: fields
+        fields: data
     );
 
     return response.successful();
   }
 
+  /*
+   * Download this attachment file
+   */
   Future<void> downloadAttachment() async {
 
     await InvenTreeAPI().downloadFile(attachment);

lib/inventree/part.dart

@@ -422,6 +422,9 @@ class InvenTreePartAttachment extends InvenTreeAttachment {
 
   InvenTreePartAttachment.fromJson(Map<String, dynamic> json) : super.fromJson(json);
 
+  @override
+  String get REFERENCE_FIELD => "part";
+
   @override
   String get URL => "part/attachment/";
 

lib/widget/attachment_widget.dart

@@ -1,33 +1,42 @@
+/*
+ * A generic widget for displaying a list of attachments.
+ *
+ * To allow use with different "types" of attachments,
+ * we pass a subclassed instance of the InvenTreeAttachment model.
+ */
+
 import "dart:io";
 
 import "package:flutter/material.dart";
 import "package:font_awesome_flutter/font_awesome_flutter.dart";
-import "package:inventree/inventree/part.dart";
+import "package:inventree/inventree/model.dart";
 import "package:inventree/widget/fields.dart";
-import "package:inventree/widget/refreshable_state.dart";
 import "package:inventree/widget/snacks.dart";
-
-import "package:inventree/api.dart";
+import "package:inventree/widget/refreshable_state.dart";
 import "package:inventree/l10.dart";
 
-class PartAttachmentsWidget extends StatefulWidget {
+class AttachmentWidget extends StatefulWidget {
 
-  const PartAttachmentsWidget(this.part, {Key? key}) : super(key: key);
+  const AttachmentWidget(this.attachment, this.referenceId, this.hasUploadPermission) : super();
 
-  final InvenTreePart part;
+  final InvenTreeAttachment attachment;
+  final int referenceId;
+  final bool hasUploadPermission;
 
   @override
-  _PartAttachmentDisplayState createState() => _PartAttachmentDisplayState(part);
+  _AttachmentWidgetState createState() => _AttachmentWidgetState(attachment, referenceId, hasUploadPermission);
 }
 
 
-class _PartAttachmentDisplayState extends RefreshableState<PartAttachmentsWidget> {
+class _AttachmentWidgetState extends RefreshableState<AttachmentWidget> {
 
-  _PartAttachmentDisplayState(this.part);
+  _AttachmentWidgetState(this.attachment, this.referenceId, this.hasUploadPermission);
 
-  final InvenTreePart part;
+  final InvenTreeAttachment attachment;
+  final int referenceId;
+  final bool hasUploadPermission;
 
-  List<InvenTreePartAttachment> attachments = [];
+  List<InvenTreeAttachment> attachments = [];
 
   @override
   String getAppBarTitle(BuildContext context) => L10().attachments;
@@ -37,20 +46,19 @@ class _PartAttachmentDisplayState extends RefreshableState<PartAttachmentsWidget
 
     List<Widget> actions = [];
 
-    if (InvenTreeAPI().checkPermission("part", "change")) {
-
+    if (hasUploadPermission) {
       // File upload
       actions.add(
-        IconButton(
-          icon: FaIcon(FontAwesomeIcons.plusCircle),
-          onPressed: () async {
-            FilePickerDialog.pickFile(
-              onPicked: (File file) {
-                upload(file);
-              }
-            );
-          },
-        )
+          IconButton(
+            icon: FaIcon(FontAwesomeIcons.plusCircle),
+            onPressed: () async {
+              FilePickerDialog.pickFile(
+                  onPicked: (File file) {
+                    upload(file);
+                  }
+              );
+            },
+          )
       );
     }
 
@@ -58,12 +66,8 @@ class _PartAttachmentDisplayState extends RefreshableState<PartAttachmentsWidget
   }
 
   Future<void> upload(File file) async {
-    final bool result = await InvenTreePartAttachment().uploadAttachment(
-      file,
-      fields: {
-        "part": "${part.pk}"
-      }
-    );
+
+    final bool result = await attachment.uploadAttachment(file, referenceId);
 
     if (result) {
       showSnackIcon(L10().uploadSuccess, success: true);
@@ -77,32 +81,31 @@ class _PartAttachmentDisplayState extends RefreshableState<PartAttachmentsWidget
   @override
   Future<void> request(BuildContext context) async {
 
-    await InvenTreePartAttachment().list(
+    await attachment.list(
       filters: {
-        "part": "${part.pk}"
+        attachment.REFERENCE_FIELD: referenceId.toString()
       }
     ).then((var results) {
 
       attachments.clear();
 
       for (var result in results) {
-        if (result is InvenTreePartAttachment) {
+        if (result is InvenTreeAttachment) {
           attachments.add(result);
         }
       }
     });
-
   }
 
   @override
   Widget getBody(BuildContext context) {
     return Center(
-      child: ListView(
-        children: ListTile.divideTiles(
-          context: context,
-          tiles: attachmentTiles(context)
-        ).toList(),
-      )
+        child: ListView(
+          children: ListTile.divideTiles(
+              context: context,
+              tiles: attachmentTiles(context)
+          ).toList(),
+        )
     );
   }
 
@@ -126,14 +129,12 @@ class _PartAttachmentDisplayState extends RefreshableState<PartAttachmentsWidget
       tiles.add(ListTile(
         title: Text(L10().attachmentNone),
         subtitle: Text(
-            L10().attachmentNonePartDetail,
-            style: TextStyle(fontStyle: FontStyle.italic),
+          L10().attachmentNonePartDetail,
+          style: TextStyle(fontStyle: FontStyle.italic),
         ),
       ));
     }
 
     return tiles;
-
   }
-
-}
+}

lib/widget/part_detail.dart

@@ -6,7 +6,7 @@ import "package:inventree/app_colors.dart";
 import "package:inventree/inventree/stock.dart";
 import "package:inventree/l10.dart";
 import "package:inventree/helpers.dart";
-import "package:inventree/widget/part_attachments_widget.dart";
+import "package:inventree/widget/attachment_widget.dart";
 import "package:inventree/widget/part_notes.dart";
 import "package:inventree/widget/progress.dart";
 import "package:inventree/inventree/part.dart";
@@ -410,7 +410,10 @@ class _PartDisplayState extends RefreshableState<PartDetailWidget> {
           Navigator.push(
             context,
             MaterialPageRoute(
-              builder: (context) => PartAttachmentsWidget(part)
+              builder: (context) => AttachmentWidget(
+                  InvenTreePartAttachment(),
+                  part.pk,
+                  InvenTreeAPI().checkPermission("part", "change"))
             )
           );
         },