WIP #120 Numeric state charts

lib/entity_class/slider_entity.dart

@@ -0,0 +1,36 @@
+part of '../main.dart';
+
+class SliderEntity extends Entity {
+  SliderEntity(Map rawData) : super(rawData);
+
+  double get minValue => _getDoubleAttributeValue("min") ?? 0.0;
+  double get maxValue =>_getDoubleAttributeValue("max") ?? 100.0;
+  double get valueStep => _getDoubleAttributeValue("step") ?? 1.0;
+
+  @override
+  Widget _buildStatePart(BuildContext context) {
+    return Expanded(
+      //width: 200.0,
+      child: Row(
+        children: <Widget>[
+          SliderStateWidget(
+            expanded: true,
+          ),
+          SimpleEntityState(),
+        ],
+      ),
+    );
+  }
+
+  @override
+  Widget _buildStatePartForPage(BuildContext context) {
+    return SimpleEntityState();
+  }
+
+  @override
+  Widget _buildAdditionalControlsForPage(BuildContext context) {
+    return SliderStateWidget(
+      expanded: false,
+    );
+  }
+}