adding packages

deprecated/flutter_ast/templates/core.dart.mustache

@@ -0,0 +1,109 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/rendering.dart';
+import 'package:flutter/gestures.dart';
+
+@mustCallSuper
+class TrackedWidget extends SingleChildRenderObjectWidget {
+  TrackedWidget({
+    Key key,
+    @required Widget child,
+    @required this.controller,
+  }) : super(key: key, child: child);
+
+  final ValueNotifier<WidgetRect> controller;
+
+  @override
+  RenderObject createRenderObject(BuildContext context) {
+    return WidgetBaseRenderObject(controller);
+  }
+}
+
+@immutable
+class WidgetRect {
+  final double lastDx;
+  final double lastDy;
+  final double lastDw;
+  final double lastDh;
+
+  WidgetRect({
+    this.lastDx = 0.0,
+    this.lastDy = 0.0,
+    this.lastDw = 0.0,
+    this.lastDh = 0.0,
+  });
+
+  WidgetRect copyWith({
+    double lastDx,
+    double lastDy,
+    double lastDw,
+    double lastDh,
+  }) {
+    return WidgetRect(
+      lastDx: lastDx ?? this.lastDx,
+      lastDy: lastDy ?? this.lastDy,
+      lastDw: lastDw ?? this.lastDw,
+      lastDh: lastDh ?? this.lastDh,
+    );
+  }
+}
+
+class WidgetBaseRenderObject extends RenderProxyBox {
+  WidgetBaseRenderObject(this.controller);
+
+  final ValueNotifier<WidgetRect> controller;
+
+  @override
+  void paint(PaintingContext context, Offset offset) {
+    assert(!debugNeedsLayout);
+    final current = controller.value;
+    controller.value = current.copyWith(lastDx: offset.dx);
+    controller.value = current.copyWith(lastDy: offset.dy);
+    controller.value = current.copyWith(lastDw: size.width);
+    controller.value = current.copyWith(lastDh: size.height);
+    super.paint(context, offset);
+  }
+}
+
+
+abstract class Core<T> {
+  dynamic get data;
+  ValueChanged<dynamic> get changed;
+  T get fallback;
+
+  T get value;
+  set value(T val);
+
+  String get name => data == null ? null : data['name'];
+  String get type => data == null ? null : data['type'];
+
+  dynamic toCode();
+  dynamic toJson();
+}
+
+class BaseCore<T> extends Core<T> {
+  BaseCore(this.data, this.changed);
+
+  @override
+  Map<String, dynamic> data;
+
+  @override
+  final VoidCallback changed;
+
+   @override
+  T get value {
+    if (data == null || data['value'] == null) {
+      return fallback;
+    }
+    return data['value'];
+  }
+
+  @override
+  set value(T val) {
+    if (val == value) {
+      return;
+    }
+    data = {'type': type, 'value': val};
+    changed();
+  }
+}