Display purcahse price for stock item

assets/release_notes.md

@@ -9,6 +9,7 @@
 - Improvements for PartCategory editing form
 - Improvements for StockLocation editing form
 - Adds ability to edit StockItem
+- Display purchase price (where available) for StockItem
 - Updated translations 
 
 ### 0.2.10 - July 2021

lib/inventree/stock.dart

@@ -60,6 +60,8 @@ class InvenTreeStockItem extends InvenTreeModel {
 
   String statusLabel(BuildContext context) {
 
+    // TODO: Delete me - The translated status values are provided by the API!
+
     switch (status) {
       case OK:
         return L10().ok;
@@ -220,6 +222,15 @@ class InvenTreeStockItem extends InvenTreeModel {
 
   int get partId => jsondata['part'] ?? -1;
 
+  String get purchasePrice => jsondata['purchase_price'];
+
+  bool get hasPurchasePrice {
+
+    String pp = purchasePrice;
+
+    return pp.isNotEmpty && pp.trim() != "-";
+  }
+
   int get trackingItemCount => (jsondata['tracking_items'] ?? 0) as int;
 
   // Date of last update

lib/widget/stock_detail.dart

@@ -534,6 +534,18 @@ class _StockItemDisplayState extends RefreshableState<StockDetailWidget> {
       );
     }
 
+    if (item.hasPurchasePrice) {
+      tiles.add(
+        ListTile(
+          title: Text(L10().purchasePrice),
+          leading: FaIcon(FontAwesomeIcons.dollarSign),
+          trailing: Text(item.purchasePrice),
+        )
+      );
+    }
+
+    // TODO - Is this stock item linked to a PurchaseOrder?
+
     // TODO - Re-enable stock item history display
     if (false && item.trackingItemCount > 0) {
       tiles.add(