Merge branch 'master' of github.com:UnityTech/UIWidgets into dev

README-ZH.md

 ## 使用要求
 
 #### Unity
-安装 Unity 2018.3 或更高版本。 你可以从[https://unity3d.com/get-unity/download](https://unity3d.com/get-unity/download)下载最新的Unity。
+
+安装 **Unity 2018.4.10f1(LTS)** 或 **Unity 2019.1.14f1** 及其更高版本。 你可以从[https://unity3d.com/get-unity/download](https://unity3d.com/get-unity/download)下载最新的Unity。
 
 #### UIWidgets包
 

README.md

 The official website of Unity Chinese Documentation (https://connect.unity.com/doc) is powered by UIWidgets and
 open-sourced @https://github.com/UnityTech/DocCN.
 
-## Requirement
+## Requirements
-Install **Unity 2018.3** or above. You can download the latest Unity on https://unity3d.com/get-unity/download.
+
+Install **Unity 2018.4.10f1 (LTS)** or **Unity 2019.1.14f1** and above. You can download the latest Unity on https://unity3d.com/get-unity/download.
 
 #### UIWidgets Package
 Visit our Github repository https://github.com/UnityTech/UIWidgets

Runtime/cupertino/route.cs

         );
 
         public static readonly DecorationTween _kGradientShadowTween = new DecorationTween(
+            begin: _CupertinoEdgeShadowDecoration.none,
             end: new _CupertinoEdgeShadowDecoration(
                 edgeGradient: new LinearGradient(
                     begin: new Alignment(0.9f, 0.0f),
                 barrierDismissible: false,
                 barrierColor: _kModalBarrierColor,
                 transitionDuration: new TimeSpan(0, 0, 0, 0, 250),
-                pageBuilder: (BuildContext _context, Animation<float> animation, Animation<float> secondaryAnimation) => {
+                pageBuilder:
+                (BuildContext _context, Animation<float> animation, Animation<float> secondaryAnimation) => {
                     return builder(_context);
                 },
                 transitionBuilder: _buildCupertinoDialogTransitions
 
         public readonly LinearGradient edgeGradient;
 
-        static _CupertinoEdgeShadowDecoration lerp(
+        static _CupertinoEdgeShadowDecoration lerpCupertino(
             _CupertinoEdgeShadowDecoration a,
             _CupertinoEdgeShadowDecoration b,
             float t
 
         public override Decoration lerpFrom(Decoration a, float t) {
             if (!(a is _CupertinoEdgeShadowDecoration)) {
-                return lerp(null, this, t);
+                return lerpCupertino(null, this, t);
-            return lerp(a, this, t);
+            return lerpCupertino((_CupertinoEdgeShadowDecoration) a, this, t);
-                return lerp(this, null, t);
+                return lerpCupertino(this, null, t);
-            return lerp(this, b, t);
+            return lerpCupertino(this, (_CupertinoEdgeShadowDecoration) b, t);
         }
 
         public override BoxPainter createBoxPainter(VoidCallback onChanged = null) {

Runtime/material/bottom_navigation_bar.cs

                     child: text
                 );
             }
-            else if (this.showUnselectedLabels) {
+            else if (!this.showUnselectedLabels) {
                 text = new FadeTransition(
                     opacity: this.animation,
                     child: text
             Color backgroundColor = null;
             switch (this.widget.type) {
                 case BottomNavigationBarType.fix:
+                    backgroundColor = this.widget.backgroundColor;
                     break;
                 case BottomNavigationBarType.shifting:
                     backgroundColor = this._backgroundColor;

Runtime/rendering/sliver_multi_box_adaptor.cs

 
         public bool keepAlive = false;
 
-        internal bool _keptAlive = false;
+        public bool keptAlive {
+            get { return this._keptAlive; }
+        }
+        internal bool _keptAlive = false;
+        
         public override string ToString() {
             return $"index={this.index}; {(this.keepAlive ? "keeyAlive; " : "")}{base.ToString()}";
         }
         }
 
         public override void insert(RenderBox child, RenderBox after = null) {
+            D.assert(!this._keepAliveBucket.ContainsValue(value: child));
             base.insert(child, after: after);
             D.assert(this.firstChild != null);
             D.assert(() => {

Runtime/widgets/automatic_keep_alive.cs

                 }
                 else {
                     SchedulerBinding.instance.addPostFrameCallback(timeStamp => {
+                        if (!this.mounted) {
+                            return;
+                        }
                         ParentDataElement childElement1 = this._getChildElement();
                         D.assert(childElement1 != null);
                         this._updateParentDataOfChild(childElement1);
         }
 
         ParentDataElement _getChildElement() {
+            D.assert(this.mounted);
             Element element = (Element) this.context;
             Element childElement = null;
             element.visitChildren((Element child) => { childElement = child; });

Runtime/widgets/routes.cs

             this._willPopCallbacks.Remove(callback);
         }
 
-        protected internal bool hasScopedWillPopCallback {
+        public bool hasScopedWillPopCallback {
             get { return this._willPopCallbacks.isNotEmpty(); }
         }
 

Runtime/widgets/sliver.cs

             this._currentBeforeChild = null;
             D.assert(this._currentlyUpdatingChildIndex == null);
             try {
-                int firstIndex = 0;
-                int lastIndex = 0;
-
-                if (!this._childElements.isEmpty()) {
-                    firstIndex = this._childElements.First().Key;
-                    lastIndex = this._childElements.Last().Key;
-                    if (this._didUnderflow) {
-                        lastIndex += 1;
-                    }
-                }
-
-                for (int index = firstIndex; index <= lastIndex; ++index) {
+                void processElement(int index) {
-                        this._currentBeforeChild = (RenderBox) newChild.renderObject;
+                        var parentData = (SliverMultiBoxAdaptorParentData) newChild.renderObject.parentData;
+                        if (!parentData.keptAlive) {
+                            this._currentBeforeChild = (RenderBox) newChild.renderObject;
+                        }
+                }
+                // processElement may modify the Map - need to do a .toList() here.
+                this._childElements.Keys.ToList().ForEach(action: processElement);
+                if (this._didUnderflow) {
+                    var lastKey = this._childElements?.Last().Key ?? -1;
+                    processElement(lastKey + 1);
                 }
             }
             finally {

Tests/Resources/Emoji.png.meta

     wrapU: -1
     wrapV: -1
     wrapW: -1
-  nPOTScale: 1
+  nPOTScale: 0
   lightmap: 0
   compressionQuality: 50
   spriteMode: 0
   platformSettings:
   - serializedVersion: 2
     buildTarget: DefaultTexturePlatform
-    maxTextureSize: 2048
+    maxTextureSize: 8192
+    resizeAlgorithm: 0
+    textureFormat: -1
+    textureCompression: 1
+    compressionQuality: 50
+    crunchedCompression: 0
+    allowsAlphaSplitting: 0
+    overridden: 0
+    androidETC2FallbackOverride: 0
+  - serializedVersion: 2
+    buildTarget: Standalone
+    maxTextureSize: 8192
+    resizeAlgorithm: 0
+    textureFormat: -1
+    textureCompression: 1
+    compressionQuality: 50
+    crunchedCompression: 0
+    allowsAlphaSplitting: 0
+    overridden: 0
+    androidETC2FallbackOverride: 0
+  - serializedVersion: 2
+    buildTarget: iPhone
+    maxTextureSize: 8192
+    resizeAlgorithm: 0
+    textureFormat: -1
+    textureCompression: 1
+    compressionQuality: 50
+    crunchedCompression: 0
+    allowsAlphaSplitting: 0
+    overridden: 0
+    androidETC2FallbackOverride: 0
+  - serializedVersion: 2
+    buildTarget: Android
+    maxTextureSize: 8192
+    resizeAlgorithm: 0
+    textureFormat: -1
+    textureCompression: 1
+    compressionQuality: 50
+    crunchedCompression: 0
+    allowsAlphaSplitting: 0
+    overridden: 0
+    androidETC2FallbackOverride: 0
+  - serializedVersion: 2
+    buildTarget: WebGL
+    maxTextureSize: 8192
     resizeAlgorithm: 0
     textureFormat: -1
     textureCompression: 1