comply the canvas

Author: nb312

doc/canvas_change.png

@@ -0,0 +1,97 @@
+///
+/// Created by NieBin on 2019/1/1
+/// Github: https://github.com/nb312
+/// Email: [email protected]
+///
+
+import "package:flutter/material.dart";
+import 'SizeUtil.dart';
+import 'dart:math';
+
+const BLUE_NORMAL = Color(0xff54c5f8);
+const GREEN_NORMAL = Color(0xff6bde54);
+const BLUE_DARK2 = Color(0xff01579b);
+const BLUE_DARK1 = Color(0xff29b6f6);
+
+class OpenPainter extends CustomPainter {
+  void _drawFourShape(Canvas canvas,
+      {Offset left_top,
+      Offset right_top,
+      Offset right_bottom,
+      Offset left_bottom,
+      Size size,
+      paint}) {
+    left_top = _convertLogicSize(left_top, size);
+    right_top = _convertLogicSize(right_top, size);
+    right_bottom = _convertLogicSize(right_bottom, size);
+    left_bottom = _convertLogicSize(left_bottom, size);
+    var path1 = Path()
+      ..moveTo(left_top.dx, left_top.dy)
+      ..lineTo(right_top.dx, right_top.dy)
+      ..lineTo(right_bottom.dx, right_bottom.dy)
+      ..lineTo(left_bottom.dx, left_bottom.dy);
+    canvas.drawPath(path1, paint);
+  }
+
+  Offset _convertLogicSize(Offset off, Size size) {
+    return Offset(SizeUtil.getAxisX(off.dx), SizeUtil.getAxisY(off.dy));
+  }
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    //580*648
+    if (size.width > 1.0 && size.height > 1.0) {
+      print(">1.9");
+      SizeUtil.size = size;
+    }
+    var paint = Paint()
+      ..style = PaintingStyle.fill
+      ..color = BLUE_NORMAL
+      ..isAntiAlias = true;
+    _drawFourShape(canvas,
+        left_top: Offset(291, 178),
+        right_top: Offset(580, 458),
+        right_bottom: Offset(580, 628),
+        left_bottom: Offset(203, 267),
+        size: size,
+        paint: paint);
+    _drawFourShape(canvas,
+        left_top: Offset(156, 314),
+        right_top: Offset(312, 468),
+        right_bottom: Offset(312, 645),
+        left_bottom: Offset(70, 402),
+        size: size,
+        paint: paint);
+    paint.color = BLUE_DARK2;
+    _drawFourShape(canvas,
+        left_top: Offset(156, 314),
+        right_top: Offset(245, 402),
+        right_bottom: Offset(4, 643),
+        left_bottom: Offset(4, 467),
+        size: size,
+        paint: paint);
+    paint.color = BLUE_DARK1;
+    _drawFourShape(canvas,
+        left_top: Offset(156, 314),
+        right_top: Offset(245, 402),
+        right_bottom: Offset(157, 490),
+        left_bottom: Offset(70, 402),
+        size: size,
+        paint: paint);
+    var circleCenter = Offset(SizeUtil.getAxisX(294), SizeUtil.getAxisY(175));
+    paint.color = BLUE_NORMAL;
+    canvas.drawCircle(circleCenter, SizeUtil.getAxisBoth(174), paint);
+    paint.color = GREEN_NORMAL;
+    canvas.drawCircle(circleCenter, SizeUtil.getAxisBoth(124), paint);
+    paint.color = Colors.white;
+    canvas.drawCircle(circleCenter, SizeUtil.getAxisBoth(80), paint);
+    canvas.save();
+    canvas.restore();
+
+//    _drawFourShape(canvas, left_top: Offset(291, 178));
+//    canvas.drawPath(path1, paint);
+  }
+
+  @override
+  bool shouldRepaint(CustomPainter oldDelegate) => false;
+}

doc/circle_note.png

@@ -0,0 +1,46 @@
+///
+/// Created by NieBin on 2018/12/26
+/// Github: https://github.com/nb312
+/// Email: [email protected]
+///
+import 'package:flutter/material.dart';
+import 'dart:math';
+
+class SizeUtil {
+  static const _DESIGN_WIDTH = 580;
+  static const _DESIGN_HEIGHT = 648;
+
+  //logic size in device
+  static Size _logicSize;
+
+  //device pixel radio.
+
+  static get width {
+    return _logicSize.width;
+  }
+
+  static get height {
+    return _logicSize.height;
+  }
+
+  static set size(size) {
+    _logicSize = size;
+  }
+
+  //@param w is the design w;
+  static double getAxisX(double w) {
+    return (w * width) / _DESIGN_WIDTH;
+  }
+
+// the y direction
+  static double getAxisY(double h) {
+    return (h * height) / _DESIGN_HEIGHT;
+  }
+
+  // diagonal direction value with design size s.
+  static double getAxisBoth(double s) {
+    return s *
+        sqrt((width * width + height * height) /
+            (_DESIGN_WIDTH * _DESIGN_WIDTH + _DESIGN_HEIGHT * _DESIGN_HEIGHT));
+  }
+}

doc/flutter_note.png

@@ -1,111 +1,45 @@
 import 'package:flutter/material.dart';
+import 'OpenPainter.dart';
+import 'package:flutter_canvas/SizeUtil.dart';
 
 void main() => runApp(MyApp());
 
 class MyApp extends StatelessWidget {
-  // This widget is the root of your application.
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
-      title: 'Flutter Demo',
+      title: 'Flutter Canvas',
       theme: ThemeData(
-        // This is the theme of your application.
-        //
-        // Try running your application with "flutter run". You'll see the
-        // application has a blue toolbar. Then, without quitting the app, try
-        // changing the primarySwatch below to Colors.green and then invoke
-        // "hot reload" (press "r" in the console where you ran "flutter run",
-        // or simply save your changes to "hot reload" in a Flutter IDE).
-        // Notice that the counter didn't reset back to zero; the application
-        // is not restarted.
         primarySwatch: Colors.blue,
       ),
-      home: MyHomePage(title: 'Flutter Demo Home Page'),
+      home: HomePage(),
     );
   }
 }
 
-class MyHomePage extends StatefulWidget {
-  MyHomePage({Key key, this.title}) : super(key: key);
-
-  // This widget is the home page of your application. It is stateful, meaning
-  // that it has a State object (defined below) that contains fields that affect
-  // how it looks.
-
-  // This class is the configuration for the state. It holds the values (in this
-  // case the title) provided by the parent (in this case the App widget) and
-  // used by the build method of the State. Fields in a Widget subclass are
-  // always marked "final".
-
-  final String title;
-
+class HomePage extends StatefulWidget {
   @override
-  _MyHomePageState createState() => _MyHomePageState();
+  _HomeState createState() => _HomeState();
 }
 
-class _MyHomePageState extends State<MyHomePage> {
-  int _counter = 0;
-
-  void _incrementCounter() {
-    setState(() {
-      // This call to setState tells the Flutter framework that something has
-      // changed in this State, which causes it to rerun the build method below
-      // so that the display can reflect the updated values. If we changed
-      // _counter without calling setState(), then the build method would not be
-      // called again, and so nothing would appear to happen.
-      _counter++;
-    });
-  }
-
+class _HomeState extends State<HomePage> {
   @override
   Widget build(BuildContext context) {
-    // This method is rerun every time setState is called, for instance as done
-    // by the _incrementCounter method above.
-    //
-    // The Flutter framework has been optimized to make rerunning build methods
-    // fast, so that you can just rebuild anything that needs updating rather
-    // than having to individually change instances of widgets.
+    SizeUtil.size = MediaQuery.of(context).size;
     return Scaffold(
       appBar: AppBar(
-        // Here we take the value from the MyHomePage object that was created by
-        // the App.build method, and use it to set our appbar title.
-        title: Text(widget.title),
+        title: Text("First Canvas"),
       ),
-      body: Center(
-        // Center is a layout widget. It takes a single child and positions it
-        // in the middle of the parent.
-        child: Column(
-          // Column is also layout widget. It takes a list of children and
-          // arranges them vertically. By default, it sizes itself to fit its
-          // children horizontally, and tries to be as tall as its parent.
-          //
-          // Invoke "debug painting" (press "p" in the console, choose the
-          // "Toggle Debug Paint" action from the Flutter Inspector in Android
-          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
-          // to see the wireframe for each widget.
-          //
-          // Column has various properties to control how it sizes itself and
-          // how it positions its children. Here we use mainAxisAlignment to
-          // center the children vertically; the main axis here is the vertical
-          // axis because Columns are vertical (the cross axis would be
-          // horizontal).
-          mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
-            Text(
-              'You have pushed the button this many times:',
-            ),
-            Text(
-              '$_counter',
-              style: Theme.of(context).textTheme.display1,
-            ),
-          ],
+      body: Container(
+          child: Center(
+        child: Container(
+          width: 280,
+          height: 320.0,
+          child: CustomPaint(
+            painter: OpenPainter(),
+          ),
         ),
-      ),
-      floatingActionButton: FloatingActionButton(
-        onPressed: _incrementCounter,
-        tooltip: 'Increment',
-        child: Icon(Icons.add),
-      ), // This trailing comma makes auto-formatting nicer for build methods.
+      )),
     );
   }
 }