Implement TypographyDemo.

Samples/UIWidgetsGallery/gallery/demos.cs

                     routeName: ColorsDemo.routeName,
                     buildRoute: (BuildContext context) => new ColorsDemo()
                 ),
-//                new GalleryDemo(
-//                    title: "Typography",
-//                    subtitle: "All of the predefined text styles",
-//                    icon: GalleryIcons.custom_typography,
-//                    category: GalleryDemoCategory._kStyle,
-//                    routeName: TypographyDemo.routeName,
-//                    buildRoute: (BuildContext context) => TypographyDemo()
-//                ),
+                new GalleryDemo(
+                    title: "Typography",
+                    subtitle: "All of the predefined text styles",
+                    icon: GalleryIcons.custom_typography,
+                    category: DemoUtils._kStyle,
+                    routeName: TypographyDemo.routeName,
+                    buildRoute: (BuildContext context) => new TypographyDemo()
+                ),
 //
 //                // Material Components
 //                new GalleryDemo(

Samples/UIWidgetsGallery/demo/typography_demo.cs

+using System.Collections.Generic;
+using Unity.UIWidgets.foundation;
+using Unity.UIWidgets.material;
+using Unity.UIWidgets.painting;
+using Unity.UIWidgets.rendering;
+using Unity.UIWidgets.widgets;
+
+namespace UIWidgetsGallery.gallery {
+    public class TextStyleItem : StatelessWidget {
+        public TextStyleItem(
+            Key key = null,
+            string name = null,
+            TextStyle style = null,
+            string text = null
+        ) : base(key: key) {
+            D.assert(name != null);
+            D.assert(style != null);
+            D.assert(text != null);
+            this.name = name;
+            this.style = style;
+            this.text = text;
+        }
+
+        public readonly string name;
+        public readonly TextStyle style;
+        public readonly string text;
+
+        public override Widget build(BuildContext context) {
+            ThemeData theme = Theme.of(context);
+            TextStyle nameStyle = theme.textTheme.caption.copyWith(color: theme.textTheme.caption.color);
+            return new Padding(
+                padding: EdgeInsets.symmetric(horizontal: 8.0f, vertical: 16.0f),
+                child: new Row(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: new List<Widget> {
+                        new SizedBox(
+                            width: 72.0f,
+                            child: new Text(this.name, style: nameStyle)
+                        ),
+                        new Expanded(
+                            child: new Text(this.text, style: this.style.copyWith(height: 1.0f))
+                        )
+                    }
+                )
+            );
+        }
+    }
+
+    public class TypographyDemo : StatelessWidget {
+        public const string routeName = "/typography";
+
+        public override Widget build(BuildContext context) {
+            TextTheme textTheme = Theme.of(context).textTheme;
+            List<Widget> styleItems = new List<Widget> {
+                new TextStyleItem(name: "Display 3", style: textTheme.display3, text: "Regular 56sp"),
+                new TextStyleItem(name: "Display 2", style: textTheme.display2, text: "Regular 45sp"),
+                new TextStyleItem(name: "Display 1", style: textTheme.display1, text: "Regular 34sp"),
+                new TextStyleItem(name: "Headline", style: textTheme.headline, text: "Regular 24sp"),
+                new TextStyleItem(name: "Title", style: textTheme.title, text: "Medium 20sp"),
+                new TextStyleItem(name: "Subheading", style: textTheme.subhead, text: "Regular 16sp"),
+                new TextStyleItem(name: "Body 2", style: textTheme.body2, text: "Medium 14sp"),
+                new TextStyleItem(name: "Body 1", style: textTheme.body1, text: "Regular 14sp"),
+                new TextStyleItem(name: "Caption", style: textTheme.caption, text: "Regular 12sp"),
+                new TextStyleItem(name: "Button", style: textTheme.button, text: "MEDIUM (ALL CAPS) 14sp")
+            };
+
+            if (MediaQuery.of(context).size.width > 500.0f) {
+                styleItems.Insert(0, new TextStyleItem(
+                    name: "Display 4",
+                    style: textTheme.display4,
+                    text: "Light 112sp"
+                ));
+            }
+
+            return new Scaffold(
+                appBar: new AppBar(title: new Text("Typography")),
+                body: new SafeArea(
+                    top: false,
+                    bottom: false,
+                    child: new ListView(children: styleItems)
+                )
+            );
+        }
+    }
+}

Samples/UIWidgetsGallery/demo/typography_demo.cs.meta

+fileFormatVersion: 2
+guid: ec695ed4b0de477a8f58aebe079b8ac0
+timeCreated: 1553075802