fix navigator bugs

add more widgets samples

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

         public static Future<T> pushNamed<T>(BuildContext context, string routeName, object arguments = null) {
             return of(context).pushNamed<T>(routeName, arguments: arguments);
         }
+        
+        public static Future pushNamed(BuildContext context, string routeName, object arguments = null) {
+            return of(context).pushNamed(routeName, arguments: arguments);
+        }
 
         public static Future<T> pushReplacementNamed<T,TO>(BuildContext context, string routeName,
             TO result = default , object arguments = null) {
                 name: name,
                 arguments: arguments
             );
-            Route<T> route = widget.onGenerateRoute(settings) as Route<T>;
+
+            var routeee = widget.onGenerateRoute(settings);
+            Route<T> route = routeee as Route<T>;
             if (route == null && !allowNull) {
                 D.assert(() => {
                     if (widget.onUnknownRoute == null) {
             object arguments = null
         ) {
             return push<T>(_routeNamed<T>(routeName, arguments: arguments));
+        }
+        
+        public Future pushNamed(
+            string routeName,
+            object arguments = null
+        ) {
+            return push(_routeNamed(routeName, arguments: arguments));
         }
 
         public Future<T> pushReplacementNamed<T, TO>(

Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/LongPressSample.cs

+using uiwidgets;
+using Unity.UIWidgets.engine2;
+using Unity.UIWidgets.widgets;
+using UnityEngine;
+
+namespace UIWidgetsSample {
+    public class LongPressSample : UIWidgetsPanel {
+        protected override void main() {
+            ui_.runApp(new MyApp());
+        }
+    }
+    
+    class MyApp : StatelessWidget
+    {
+        public override Widget build(BuildContext context)
+        {
+            return new WidgetsApp(
+                home: new LongPressSampleWidget(),
+                pageRouteBuilder: (settings, builder) =>
+                    new PageRouteBuilder(
+                        settings: settings,
+                        pageBuilder: (Buildcontext, animation, secondaryAnimation) => builder(context)
+                    )
+            );
+        }
+    }
+
+    public class LongPressSampleWidget : StatefulWidget {
+        public override State createState() {
+            return new _LongPressSampleWidgetState();
+        }
+    }
+
+    class _LongPressSampleWidgetState : State<LongPressSampleWidget> {
+        public override Widget build(BuildContext context) {
+            return new GestureDetector(
+                onLongPressStart: (value) => { Debug.Log($"Long Press Drag Start: {value}"); },
+                onLongPressMoveUpdate: (value) => { Debug.Log($"Long Press Drag Update: {value}"); },
+                onLongPressEnd: (value) => { Debug.Log($"Long Press Drag Up: {value}"); },
+                onLongPressUp: () => { Debug.Log($"Long Press Up"); },
+                onLongPress: () => { Debug.Log($"Long Press"); },
+                child: new Center(
+                    child: new Container(
+                        width: 200,
+                        height: 200,
+                        color: Colors.blue
+                    )
+                )
+            );
+        }
+    }
+}

Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/LongPressSample.cs.meta

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+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/NavigationSample.cs

+using System;
+using System.Collections.Generic;
+using uiwidgets;
+using Unity.UIWidgets.animation;
+using Unity.UIWidgets.engine2;
+using Unity.UIWidgets.foundation;
+using Unity.UIWidgets.gestures;
+using Unity.UIWidgets.material;
+using Unity.UIWidgets.painting;
+using Unity.UIWidgets.rendering;
+using Unity.UIWidgets.ui;
+using Unity.UIWidgets.widgets;
+using DialogUtils = Unity.UIWidgets.widgets.DialogUtils;
+using TextStyle = Unity.UIWidgets.painting.TextStyle;
+using ui_ = Unity.UIWidgets.widgets.ui_;
+
+namespace UIWidgetsSample {
+    public class NavigationSample : UIWidgetsPanel {
+
+        protected override void main()
+        {
+            ui_.runApp(new MyApp());
+        }
+        
+        
+        
+            
+        class MyApp : StatelessWidget
+        {
+            public override Widget build(BuildContext context)
+            {
+                return new WidgetsApp(
+                    initialRoute: "/",
+                    textStyle: new TextStyle(fontSize: 24),
+                    pageRouteBuilder: (settings, builder) =>
+                        new PageRouteBuilder(
+                            settings: settings,
+                            pageBuilder: (BuildContext subContext, Animation<float> animation,
+                                Animation<float> secondaryAnimation) => builder(subContext),
+                            transitionsBuilder: (BuildContext subContext, Animation<float>
+                                    animation, Animation<float> secondaryAnimation, Widget child) =>
+                                new _FadeUpwardsPageTransition(
+                                    routeAnimation: animation,
+                                    child: child
+                                )
+                        ),
+                    routes: new Dictionary<string, WidgetBuilder> {
+                        {"/", (subContext) => new HomeScreen()},
+                        {"/detail", (subContext) => new DetailScreen()}
+                    }
+                );
+            }
+        }
+    }
+    
+    public class CustomButton : StatelessWidget {
+        public CustomButton(
+            Key key = null,
+            GestureTapCallback onPressed = null,
+            EdgeInsets padding = null,
+            Color backgroundColor = null,
+            Widget child = null
+        ) : base(key: key) {
+            this.onPressed = onPressed;
+            this.padding = padding ?? EdgeInsets.all(8.0f);
+            this.backgroundColor = backgroundColor ?? Colors.white;
+            this.child = child;
+        }
+
+        public readonly GestureTapCallback onPressed;
+        public readonly EdgeInsets padding;
+        public readonly Widget child;
+        public readonly Color backgroundColor;
+
+        public override Widget build(BuildContext context) {
+            return new GestureDetector(
+                onTap: this.onPressed,
+                child: new Container(
+                    padding: this.padding,
+                    color: this.backgroundColor,
+                    child: this.child
+                )
+            );
+        }
+    }
+
+
+    class HomeScreen : StatelessWidget {
+        public override Widget build(BuildContext context) {
+            return new NavigationPage(
+                body: new Container(
+                    color: new Color(0xFF888888),
+                    child: new Center(
+                        child: new CustomButton(onPressed: () => { Navigator.pushNamed(context, "/detail"); },
+                            child: new Text("Go to Detail"))
+                    )),
+                title: "Home"
+            );
+        }
+    }
+
+    class DetailScreen : StatelessWidget {
+        public override Widget build(BuildContext context) {
+            return new NavigationPage(
+                body: new Container(
+                    color: new Color(0xFF1389FD),
+                    child: new Center(
+                        child: new Column(
+                            children: new List<Widget>() {
+                                new CustomButton(onPressed: () => { Navigator.pop<object>(context); }, child: new Text("Back")),
+                                new CustomButton(
+                                    onPressed: () => {
+                                        _Dialog.showDialog(context, builder: (BuildContext c) => new Dialog());
+                                    }, child: new Text("Show Dialog"))
+                            }
+                        )
+                    )),
+                title: "Detail");
+        }
+    }
+
+    class Dialog : StatelessWidget {
+        public override Widget build(BuildContext context) {
+            return new Center(child: new Container(
+                color: new Color(0xFFFF0000),
+                width: 100,
+                height: 80,
+                child: new Center(
+                    child: new Text("Hello Dialog")
+                )));
+        }
+    }
+
+    class _FadeUpwardsPageTransition : StatelessWidget {
+        internal _FadeUpwardsPageTransition(
+            Key key = null,
+            Animation<float> routeAnimation = null, // The route's linear 0.0 - 1.0 animation.
+            Widget child = null
+        ) : base(key: key) {
+            this._positionAnimation = _bottomUpTween.chain(_fastOutSlowInTween).animate(routeAnimation);
+            this._opacityAnimation = _easeInTween.animate(routeAnimation);
+            this.child = child;
+        }
+
+        static Tween<Offset> _bottomUpTween = new OffsetTween(
+            begin: new Offset(0.0f, 0.25f),
+            end: Offset.zero
+        );
+
+        static Animatable<float> _fastOutSlowInTween = new CurveTween(curve: Curves.fastOutSlowIn);
+        static Animatable<float> _easeInTween = new CurveTween(curve: Curves.easeIn);
+
+        readonly Animation<Offset> _positionAnimation;
+        readonly Animation<float> _opacityAnimation;
+        public readonly Widget child;
+
+        public override Widget build(BuildContext context) {
+            return new SlideTransition(
+                position: this._positionAnimation,
+                child: new FadeTransition(
+                    opacity: this._opacityAnimation,
+                    child: this.child
+                )
+            );
+        }
+    }
+
+    class NavigationPage : StatelessWidget {
+        public readonly Widget body;
+        public readonly string title;
+
+        public NavigationPage(Widget body = null, string title = null) {
+            this.title = title;
+            this.body = body;
+        }
+
+        public override Widget build(BuildContext context) {
+            Widget back = null;
+            if (Navigator.of(context).canPop()) {
+                back = new CustomButton(onPressed: () => { Navigator.pop<object>(context); },
+                    child: new Text("Go Back"));
+                back = new Column(mainAxisAlignment: MainAxisAlignment.center, children: new List<Widget>() {back});
+            }
+
+
+            return new Container(
+                child: new Column(
+                    children: new List<Widget>() {
+                        new ConstrainedBox(constraints: new BoxConstraints(maxHeight: 80),
+                            child: new DecoratedBox(
+                                decoration: new BoxDecoration(color: new Color(0XFFE1ECF4)),
+                                child: new NavigationToolbar(leading: back,
+                                    middle: new Text(this.title, textAlign: TextAlign.center)))),
+                        new Flexible(child: this.body)
+                    }
+                )
+            );
+        }
+    }
+
+    static class _Dialog {
+        public static void showDialog(BuildContext context,
+            bool barrierDismissible = true, WidgetBuilder builder = null) {
+            DialogUtils.showGeneralDialog<object>(
+                context: context,
+                pageBuilder: (BuildContext buildContext, Animation<float> animation,
+                    Animation<float> secondaryAnimation) => {
+                    return builder(buildContext);
+                },
+                barrierDismissible: barrierDismissible,
+                barrierColor: new Color(0x8A000000),
+                transitionDuration: TimeSpan.FromMilliseconds(150),
+                transitionBuilder: _buildMaterialDialogTransitions
+            );
+        }
+
+        static Widget _buildMaterialDialogTransitions(BuildContext context,
+            Animation<float> animation, Animation<float> secondaryAnimation, Widget child) {
+            return new FadeTransition(
+                opacity: new CurvedAnimation(
+                    parent: animation,
+                    curve: Curves.easeOut
+                ),
+                child: child
+            );
+        }
+    }
+}

Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/NavigationSample.cs.meta

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Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/PageViewSample.cs

+using System.Collections.Generic;
+using Unity.UIWidgets.engine2;
+using Unity.UIWidgets.ui;
+using Unity.UIWidgets.widgets;
+using ui_ = Unity.UIWidgets.widgets.ui_;
+
+namespace UIWidgetsSample {
+    public class PageViewSample : UIWidgetsPanel {
+            
+        protected override void main()
+        {
+            ui_.runApp(new MyApp());
+        }
+        
+        class MyApp : StatelessWidget
+        {
+            public override Widget build(BuildContext context)
+            {
+                return new WidgetsApp(
+                    home: new Container(
+                        width: 200,
+                        height: 400,
+                        child: new PageView(
+                            children: new List<Widget>() {
+                                new Container(
+                                    color: new Color(0xFFE91E63)
+                                ),
+                                new Container(
+                                    color: new Color(0xFF00BCD4)
+                                ),
+                                new Container(
+                                    color: new Color(0xFF673AB7)
+                                )
+                            }
+                        )),
+                    pageRouteBuilder: (settings, builder) =>
+                        new PageRouteBuilder(
+                            settings: settings,
+                            pageBuilder: (Buildcontext, animation, secondaryAnimation) => builder(context)
+                        )
+                );
+            }
+        }
+    }
+}

Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/PageViewSample.cs.meta

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Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/ScrollbarSample.cs

+using System.Collections.Generic;
+using Unity.UIWidgets.engine2;
+using Unity.UIWidgets.material;
+using Unity.UIWidgets.painting;
+using Unity.UIWidgets.ui;
+using Unity.UIWidgets.widgets;
+using ui_ = Unity.UIWidgets.widgets.ui_;
+
+namespace UIWidgetsSample {
+    public class ScrollbarSample : UIWidgetsPanel {
+        protected override void main()
+        {
+            ui_.runApp(new MyApp());
+        }
+        
+        class MyApp : StatelessWidget
+        {
+            public override Widget build(BuildContext context)
+            {
+                return new WidgetsApp(
+                    home: new Container(
+                        decoration: new BoxDecoration(
+                            border: Border.all(color: new Color(0xFFFFFF00))
+                        ),
+                        child: new Scrollbar(
+                            child: new ListView(
+                                children: new List<Widget> {
+                                    new Container(height: 40.0f, child: new Text("0")),
+                                    new Container(height: 40.0f, child: new Text("1")),
+                                    new Container(height: 40.0f, child: new Text("2")),
+                                    new Container(height: 40.0f, child: new Text("3")),
+                                    new Container(height: 40.0f, child: new Text("4")),
+                                    new Container(height: 40.0f, child: new Text("5")),
+                                    new Container(height: 40.0f, child: new Text("6")),
+                                    new Container(height: 40.0f, child: new Text("7")),
+                                    new Container(height: 40.0f, child: new Text("8")),
+                                    new Container(height: 40.0f, child: new Text("9")),
+                                    new Container(height: 40.0f, child: new Text("10")),
+                                    new Container(height: 40.0f, child: new Text("11")),
+                                    new Container(height: 40.0f, child: new Text("12")),
+                                    new Container(height: 40.0f, child: new Text("13")),
+                                    new Container(height: 40.0f, child: new Text("14")),
+                                    new Container(height: 40.0f, child: new Text("15")),
+                                    new Container(height: 40.0f, child: new Text("16")),
+                                    new Container(height: 40.0f, child: new Text("17")),
+                                }
+                            )
+                        )
+                    ),
+                    pageRouteBuilder: (settings, builder) =>
+                        new PageRouteBuilder(
+                            settings: settings,
+                            pageBuilder: (Buildcontext, animation, secondaryAnimation) => builder(context)
+                        )
+                );
+            }
+        }
+    }
+}

Samples/UIWidgetsSamples_2019_4/Assets/WidgetsSample/ScrollbarSample.cs.meta

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