Merge pull request #1 from alekskuzmin/master

Migrated to null safety

CHANGELOG.md

@@ -1,3 +1,8 @@
+## [0.3.0] - 2021-04-09
+
+### Null safety
+The package is now null-safe. Added a static function in a Smoothie class for convenient import.
+
 ## [0.2.0+1] - 2020-05-12
 
 ### Breaking changes

README.md

@@ -2,7 +2,7 @@
 
 # smoothie
 
-Create and sample a smooth bezier curve going through a given set of points
+Create and sample a smooth Bézier curve going through a given set of points
 
 ## Usage
 
@@ -38,3 +38,130 @@ List<Point<num>> _sampledCurve = _originalDataSeries.smooth(_sampleCount);
 See oversampling in action:
 
 <img src="https://raw.githubusercontent.com/alekskuzmin/smoothie/master/example/example.gif" width="270" height="480">
+
+Full example using the `charts_flutter` package:
+
+```dart
+import 'dart:math';
+
+import 'package:charts_flutter/flutter.dart' as charts;
+import 'package:flutter/material.dart';
+import 'package:smoothie/smoothie.dart';
+
+void main() => runApp(MyApp());
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'Smoothie Demo',
+      theme: ThemeData(
+        primarySwatch: Colors.teal,
+      ),
+      home: SmoothieHomePage(),
+    );
+  }
+}
+
+class SmoothieHomePage extends StatefulWidget {
+  SmoothieHomePage({Key? key}) : super(key: key);
+
+  @override
+  _SmoothieHomePageState createState() => _SmoothieHomePageState();
+}
+
+class _SmoothieHomePageState extends State<SmoothieHomePage> {
+  int _samplingPointCount = 0;
+
+  var _originalDataSeries = <Point>[
+    Point(0, 5),
+    Point(2, 15),
+    Point(3, 10),
+    Point(8, 6),
+    Point(9, 13),
+  ];
+
+  @override
+  void initState() {
+    super.initState();
+    _samplingPointCount = _originalDataSeries.length;
+  }
+
+  void _incrementCounter() {
+    setState(() {
+      _samplingPointCount++;
+    });
+  }
+
+  void _decrementCounter() {
+    setState(() {
+      if (_samplingPointCount > _originalDataSeries.length)
+        _samplingPointCount--;
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    var series = [
+      new charts.Series(
+        domainFn: (Point chartData, _) => chartData.x,
+        measureFn: (Point chartData, _) => chartData.y,
+        colorFn: (Point point, _) => charts.MaterialPalette.teal.shadeDefault,
+        id: 'Example Series',
+        data: _originalDataSeries.smooth(
+          _samplingPointCount,
+        ),
+      ),
+    ];
+
+    var chart = new charts.LineChart(
+      series,
+      animate: false,
+      defaultRenderer: new charts.LineRendererConfig(
+        includeArea: true,
+      ),
+    );
+
+    return Scaffold(
+        appBar: AppBar(
+          title: Text("Smoothie Demo"),
+        ),
+        body: Center(
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: <Widget>[
+              Text(
+                'The smooth curve now has $_samplingPointCount points.',
+              ),
+              Container(
+                height: 200,
+                child: chart,
+              ),
+            ],
+          ),
+        ),
+        floatingActionButton: Row(
+          mainAxisAlignment: MainAxisAlignment.end,
+          children: <Widget>[
+            FloatingActionButton(
+              onPressed: _decrementCounter,
+              tooltip: 'Decrement',
+              child: Icon(Icons.remove),
+            ),
+            FloatingActionButton(
+              onPressed: _incrementCounter,
+              tooltip: 'Increment',
+              child: Icon(Icons.add),
+            ),
+          ],
+        ));
+  }
+}
+```
+
+If you want to run the example as is and you are using null safety, you have to pass `--no-sound-null-safety` to the build command as the current version of `charts_flutter` does not yet support null safety:
+```console
+cd example
+flutter run --no-sound-null-safety
+```
+

example/lib/main.dart

@@ -14,15 +14,13 @@ class MyApp extends StatelessWidget {
       theme: ThemeData(
         primarySwatch: Colors.teal,
       ),
-      home: SmoothieHomePage(title: 'Smoothie Demo'),
+      home: SmoothieHomePage(),
     );
   }
 }
 
 class SmoothieHomePage extends StatefulWidget {
-  SmoothieHomePage({Key key, this.title}) : super(key: key);
-
-  final String title;
+  SmoothieHomePage({Key? key}) : super(key: key);
 
   @override
   _SmoothieHomePageState createState() => _SmoothieHomePageState();
@@ -31,7 +29,7 @@ class SmoothieHomePage extends StatefulWidget {
 class _SmoothieHomePageState extends State<SmoothieHomePage> {
   int _samplingPointCount = 0;
 
-  var originalDataSeries = <Point>[
+  var _originalDataSeries = <Point>[
     Point(0, 5),
     Point(2, 15),
     Point(3, 10),
@@ -42,7 +40,7 @@ class _SmoothieHomePageState extends State<SmoothieHomePage> {
   @override
   void initState() {
     super.initState();
-    _samplingPointCount = originalDataSeries.length;
+    _samplingPointCount = _originalDataSeries.length;
   }
 
   void _incrementCounter() {
@@ -53,7 +51,7 @@ class _SmoothieHomePageState extends State<SmoothieHomePage> {
 
   void _decrementCounter() {
     setState(() {
-      if (_samplingPointCount > originalDataSeries.length)
+      if (_samplingPointCount > _originalDataSeries.length)
         _samplingPointCount--;
     });
   }
@@ -66,7 +64,7 @@ class _SmoothieHomePageState extends State<SmoothieHomePage> {
         measureFn: (Point chartData, _) => chartData.y,
         colorFn: (Point point, _) => charts.MaterialPalette.teal.shadeDefault,
         id: 'Example Series',
-        data: originalDataSeries.smooth(
+        data: _originalDataSeries.smooth(
           _samplingPointCount,
         ),
       ),
@@ -82,7 +80,7 @@ class _SmoothieHomePageState extends State<SmoothieHomePage> {
 
     return Scaffold(
         appBar: AppBar(
-          title: Text(widget.title),
+          title: Text("Smoothie Demo"),
         ),
         body: Center(
           child: Column(