Allow model class to be filtered

- Each subclass should provide a custom filtering function

lib/inventree/model.dart

@@ -142,6 +142,25 @@ class InvenTreeModel {
 
   // TODO - Define a 'save' / 'update' function
 
+  // Override this function for each sub-class
+  bool matchAgainstString(String filter) => false;
+
+  // Filter this item against a list of provided filters
+  // Each filter must be matched
+  // Used for (e.g.) filtering returned results
+  bool filter(String filterString) {
+
+    List<String> filters = filterString.trim().toLowerCase().split(" ");
+
+    for (var f in filters) {
+      if (!matchAgainstString(f)) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
 
 }
 

lib/inventree/stock.dart

@@ -44,6 +44,15 @@ class InvenTreeStockLocation extends InvenTreeModel {
     var loc = InvenTreeStockLocation.fromJson(json);
 
     return loc;
+  }
 
+  @override
+  bool matchAgainstString(String filter) {
+
+    if (name.toLowerCase().contains(filter)) return true;
+
+    if (description.toLowerCase().contains(filter)) return true;
+
+    return false;
   }
 }

lib/widget/location_display.dart

@@ -28,6 +28,17 @@ class _LocationDisplayState extends State<LocationDisplayWidget> {
 
   List<InvenTreeStockLocation> _sublocations = List<InvenTreeStockLocation>();
 
+  String _locationFilter = '';
+
+  List<InvenTreeStockLocation> get sublocations {
+    
+    if (_locationFilter.isEmpty || _sublocations.isEmpty) {
+      return _sublocations;
+    } else {
+      return _sublocations.where((loc) => loc.filter(_locationFilter)).toList();
+    }
+  }
+
   List<InvenTreeStockItem> _items = List<InvenTreeStockItem>();
 
   String get _title {
@@ -86,7 +97,17 @@ class _LocationDisplayState extends State<LocationDisplayWidget> {
               textAlign: TextAlign.left,
               style: TextStyle(fontWeight: FontWeight.bold),
             ),
-            Expanded(child: SublocationList(_sublocations)),
+            TextField(
+              decoration: InputDecoration(
+                hintText: "Filter locations",
+              ),
+              onChanged: (text) {
+                setState(() {
+                  _locationFilter = text.trim().toLowerCase();
+                });
+              },
+            ),
+            Expanded(child: SublocationList(sublocations)),
             Divider(),
             Text(
               "Stock Items - ${_items.length}",

lib/widget/stock_display.dart

@@ -27,7 +27,6 @@ class _StockItemDisplayState extends State<StockItemDisplayWidget> {
     if (item == null) {
       return "Stock Item";
     } else {
-      print(item.jsondata);
       return "Item: x ${item.partName}";
     }
   }