Merge pull request #287 from Unity-Technologies/zxw/fix_transform_hover_issue

fix transform hover issue

com.unity.uiwidgets/CHANGELOG.md

 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [2.0.4-preview.1] - 2021-12-21
+
+### Fixes
+- Android IL2CPP bbuild crash issue [\#194](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/194)
+- Fix glContext issue when showing multiple UIWidgets panels [\#209](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/209)
+- Fix the issue that hover doesn't work [\#215](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/215)
+- Fix crash caused by shadow [\#225](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/225)
+- Fix stackoverflow issue caused by static methods [\#246](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/246)
+- Fix crash caused by missing Lottie file [\#263](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/263)
+- Fix color calculation issue [\#267](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/267)
+
+### New Features
+- Add support for Raycastable panel [\#214](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/214)
+- Add support for Android arm64 build [\#221](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/221)
+- Add support for Editor drag&drop support [\#268](https://github.com/Unity-Technologies/com.unity.uiwidgets/pull/268)
+
 ## [2.0.3-preview.1] - 2021-07-02
 
 ### Fixes

com.unity.uiwidgets/Runtime/rendering/object.cs

 
         bool _needsCompositing;
 
-        public bool needsCompositing {
+        public virtual bool needsCompositing {
             get {
                 D.assert(!_needsCompositingBitsUpdate);
                 return _needsCompositing;

com.unity.uiwidgets/Runtime/rendering/proxy_box.cs

 
         public bool _annotationIsActive;
 
-        public bool needsCompositing {
+        public override bool needsCompositing {
-
+        
-                AnnotatedRegionLayer<MouseTrackerAnnotation> layer = new AnnotatedRegionLayer<MouseTrackerAnnotation>(
+                var layer = new AnnotatedRegionLayer<MouseTrackerAnnotation>(
-                    opaque: opaque // TODO
+                    opaque: opaque
                 );
                 context.pushLayer(layer, base.paint, offset);
             }

com.unity.uiwidgets/Runtime/widgets/basic.cs

             bool opaque = true,
             Widget child = null
         ) : base(key: key) {
-            D.assert(opaque != null);
             this.onEnter = onEnter;
             this.onExit = onExit;
             this.onHover = onHover;
 
         public override void updateRenderObject(BuildContext context, RenderObject renderObject) {
             RenderMouseRegion _renderObject = (RenderMouseRegion) renderObject;
-            MouseRegion widget = owner.widget;
+            MouseRegion widget = owner.widget; 
             _renderObject.onEnter = widget.onEnter;
             _renderObject.onHover = widget.onHover;
             _renderObject.onExit = owner.getHandleExit();