--- a/svghmi/widget_button.ysl2	Wed May 13 18:47:09 2020 +0200
+++ b/svghmi/widget_button.ysl2	Wed May 13 18:50:07 2020 +0200
@@ -1,18 +1,20 @@
 // widget_button.ysl2
 
-template "widget[@type='Button']", mode="widget_defs" {
-    param "hmi_element";
-    | frequency: 5,
-    | init: function() {
-    |     this.element.addEventListener(
-    |       "mousedown",
-    |       evt => {
-    |           change_hmi_value(this.indexes[0], "=1");
-    |       });
-    |     this.element.addEventListener(
-    |       "mouseup",
-    |       evt => {
-    |           change_hmi_value(this.indexes[0], "=0");
-    |       });
-    | },
-}
\ No newline at end of file
+template "widget[@type='Button']", mode="widget_class"
+    ||
+    class ButtonWidget extends Widget{
+        frequency = 5;
+        init() {
+            this.element.addEventListener(
+              "mousedown",
+              evt => {
+                  change_hmi_value(this.indexes[0], "=1");
+              });
+            this.element.addEventListener(
+              "mouseup",
+              evt => {
+                  change_hmi_value(this.indexes[0], "=0");
+              });
+        }
+    }
+    ||