refactor ForEachFunction to use the existing registry instead of crea…

examples/json_dynamic_widget_example/lib/src/issue_420_page.dart

@@ -0,0 +1,63 @@
+import 'package:json_dynamic_widget/json_dynamic_widget.dart';
+
+/// https://github.com/peiffer-innovations/json_dynamic_widget/issues/420
+class Issue420Page extends StatelessWidget {
+  Issue420Page({super.key});
+
+  final JsonWidgetData data = JsonWidgetData.fromDynamic({
+    "type": "set_value",
+    "args": {
+        "cleanup":false,
+        "values": {
+            "template": {
+                "type": "elevated_button",
+                "args": {
+                    "child": {
+                        "type": "text",
+                        "args": {
+                            "text": "\${key}"
+                        }
+                    },
+                    "onPressed": "\${set_value('myvalue','value :'+value['id'])}"
+                }
+            },
+            "myvalue": "INITIAL",
+            "array": [
+                {"id": "1"},
+                {"id": "2"},
+                {"id": "3"}
+            ]
+        },
+        "child": {
+            "type": "column",
+            "args": {
+                "children": [
+                    {
+                        "type": "text",
+                        "listen": [
+                            "myvalue"
+                        ],
+                        "args": {
+                            "text": "\${'value: ' + myvalue}"
+                        }
+                    },
+                    {
+                        "type": "column",
+                        "args": {
+                            "children": "\${for_each(array,'template')}"
+                        }
+                    }
+                ]
+            }
+        }
+    }
+});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: Text('Issue 420')),
+      body: Center(child: data.build(context: context)),
+    );
+  }
+}

examples/json_dynamic_widget_example/lib/src/launcher.dart

@@ -14,6 +14,8 @@ import 'package:json_dynamic_widget_example/src/issue_219_page.dart';
 import 'package:json_dynamic_widget_example/src/issue_220_page.dart';
 import 'package:json_dynamic_widget_example/src/issue_24_page.dart';
 import 'package:json_dynamic_widget_example/src/issue_356_page.dart';
+import 'package:json_dynamic_widget_example/src/issue_420_page.dart';
+
 import 'package:json_dynamic_widget_example/src/untestable_full_widget_page.dart';
 import 'package:logging/logging.dart';
 
@@ -257,6 +259,11 @@ class _RootPageState extends State<RootPage> {
             builder: (BuildContext context) => Issue356Page(),
           ),
         ),
+    'issue_420': (context, _) async => Navigator.of(context).push(
+          MaterialPageRoute(
+            builder: (BuildContext context) => Issue420Page(),
+          ),
+        ),
     'layout_builder': _onJsonPageSelected,
     'length': _onJsonPageSelected,
     'limited_box': _onJsonPageSelected,

packages/json_dynamic_widget/CHANGELOG.md

@@ -1,3 +1,8 @@
+## [12.0.1] - January 15th, 2026
+
+* 'for_each' function now uses the existing registry instead of creating new instances. This ensures that variables set during iteration are accessible in the broader context and resolves issues related to variable scope during iteration.
+
+
 ## [12.0.0+5] - January 13, 2026
 
 * Automated dependency updates
@@ -17,7 +22,7 @@
 
 * Automated dependency updates
 
-
+  
 ## [12.0.0+1] - November 18, 2025
 
 * Automated dependency updates
@@ -418,7 +423,6 @@ This is a huge release with several breaking changes.  It brings in the ability
 
 * Automated dependency updates
 
->>>>>>> fabcc57c6772a1015dbb260dc2cb5a28bfade292:CHANGELOG.md
 
 ## [6.1.0] - July 17th, 2023
 

packages/json_dynamic_widget/lib/src/builders/json_set_value_builder.dart

@@ -55,10 +55,11 @@ class _SetValueState extends State<_SetValue> {
   @override
   void didUpdateWidget(oldWidget) {
     super.didUpdateWidget(oldWidget);
-    oldWidget.values?.forEach(
-      (key, _) =>
-          oldWidget.data.jsonWidgetRegistry.removeValue(key, originator: null),
-    );
+    oldWidget.values?.forEach((key, _) {
+      if (widget.values?.containsKey(key) != true) {
+        oldWidget.data.jsonWidgetRegistry.removeValue(key, originator: null);
+      }
+    });
 
     widget.values?.forEach(
       (key, value) =>