add the progress indicator.

Author: nb312

lib/const/page_item_const.dart

@@ -142,4 +142,9 @@ const PAGE_ITEMS = [
     "img": PageImage.FLUTTER_OPEN,
     "click": PageName.DATA_TABLE,
   },
+  {
+    "title": PageName.PROGRESS_INDICATOR,
+    "img": PageImage.FLUTTER_OPEN,
+    "click": PageName.PROGRESS_INDICATOR,
+  },
 ];

lib/const/page_name_const.dart

@@ -33,4 +33,5 @@ class PageName {
   static const CARD = "CARD";
   static const TOOLTIP = "Tooltip";
   static const DATA_TABLE = "DataTable";
+  static const PROGRESS_INDICATOR = "ProgressIndicator";
 }

lib/main.dart

@@ -47,6 +47,7 @@ class FlutterOpenApp extends StatelessWidget {
         PageName.CARD: (context) => CardPage(),
         PageName.TOOLTIP: (context) => TooltipPage(),
         PageName.DATA_TABLE: (context) => DataTablePage(),
+        PageName.PROGRESS_INDICATOR: (context) => ProgressIndicatorPage(),
       },
     );
   }

lib/page/info/ProgressIndicatorPage.dart

@@ -0,0 +1,79 @@
+///
+/// Created by NieBin on 2019/5/17
+/// Github: https://github.com/nb312
+/// Email: [email protected]
+///
+import "package:flutter/material.dart";
+import 'package:flutter_widgets/const/_const.dart';
+
+class ProgressIndicatorPage extends StatefulWidget {
+  @override
+  ProgressIndicatorState createState() => ProgressIndicatorState();
+}
+
+class ProgressIndicatorState extends State<ProgressIndicatorPage>
+    with SingleTickerProviderStateMixin {
+  var t = Tween(begin: BLUE, end: YELLOW);
+  AnimationController _controller;
+  var pro = Tween<double>(begin: 0.0, end: 1.0);
+  var len = 0.0;
+
+  @override
+  void initState() {
+    super.initState();
+    _controller =
+        AnimationController(vsync: this, duration: Duration(seconds: 10));
+    pro.animate(_controller).addListener(() => setState(() {
+          print("len = $len");
+          len = _controller.value;
+        }));
+    _controller.forward();
+  }
+
+  Widget _lineIndicator() => Container(
+        constraints: BoxConstraints.expand(width: 100, height: 10),
+        child: LinearProgressIndicator(
+          backgroundColor: BLUE,
+          value: len,
+        ),
+      );
+
+  Widget _circleIndicator() => Container(
+        constraints: BoxConstraints.expand(width: 100, height: 100),
+        child: CircularProgressIndicator(
+          value: len,
+          backgroundColor: YELLOW,
+//          valueColor: t.animate(_controller),
+          strokeWidth: 10,
+        ),
+      );
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+        appBar: AppBar(
+          title: Text(PageName.PROGRESS_INDICATOR),
+        ),
+        body: Center(
+          child: Column(
+            children: <Widget>[
+              _lineIndicator(),
+              _circleIndicator(),
+            ],
+          ),
+        ));
+  }
+
+  @override
+  void dispose() {
+    super.dispose();
+    _controller.dispose();
+  }
+}
+//Key key,
+//    double value,
+//Color backgroundColor,
+//    Animation<Color> valueColor,
+//String semanticsLabel,
+//    String semanticsValue,
+//}

lib/page/info/_info.dart

@@ -6,3 +6,4 @@
 export "CardPage.dart";
 export "TooltipPage.dart";
 export 'DataTablePage.dart';
+export 'ProgressIndicatorPage.dart';