Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

交作业 #9

Merged
merged 6 commits into from
Dec 5, 2020
Merged

交作业 #9

Changes from all commits
Commits
Show all changes
6 commits
Select commit Hold shift + click to select a range
b011108
粗糙的实现注册表单
Dec 4, 2020
2cc909f
Update 1 - 注册表单的实现 - 20201127/ray_main.dart
cr1992 Dec 4, 2020
ac43c25
代码优化
Dec 4, 2020
faa8d1b
交作业
Dec 4, 2020
6bbdffc
Merge remote-tracking branch 'update_stream/main' into main
Dec 5, 2020
93af07a
代码优化 增加注释
Dec 5, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
223 changes: 223 additions & 0 deletions 2 - 百格齐放 - 20201202/ray_main.dart
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,223 @@
import 'package:flutter/material.dart';
import 'dart:math' as math;

void main() {
runApp(MyApp());
}

class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}

class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);

final String title;

@override
_MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
@override
Widget build(BuildContext context) {
return Scaffold(
body: OrientationBuilder(
builder: (_, orientation) {
List<Widget> children = <Widget>[
Expanded(
child: PercentBoxWidget(
max: 10,
data: [2, 5, 8, 3, 6, 9, 1, 4, 7],
),
),
Expanded(
child: StackBoxWidget(
boxCount: 10,
),
),
];
if (orientation == Orientation.landscape) {
return Row(
children: children,
);
} else {
return Column(
children: children,
);
}
},
),
);
}
}

class RandomColor {
const RandomColor._();

static final math.Random _random = math.Random();

static Color getColor() {
return Color.fromARGB(
255,
_random.nextInt(255),
_random.nextInt(255),
_random.nextInt(255),
);
}
}

class PercentBoxWidget extends LeafRenderObjectWidget {
final int max;
final List<int> data;

PercentBoxWidget({
this.max = 10,
this.data = const <int>[],
}) : assert(max != null && max > 1),
assert(() {
if (data == null) {
return false;
}
data.forEach((element) {
assert(element > 0 && element < max);
});
return true;
}());

@override
RenderPercentBox createRenderObject(BuildContext context) {
return RenderPercentBox(max, data);
}

@override
void updateRenderObject(
BuildContext context, covariant RenderPercentBox renderPercentBox) {
renderPercentBox
..data = data
..max = max;
}
}

class RenderPercentBox extends RenderBox {
int max;
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

想法不错，但是为什么不是终值？

List<int> data;
final Paint bgPaint = Paint()..isAntiAlias = true; //背景画笔
final TextPainter textPainter =
TextPainter(textDirection: TextDirection.ltr); //文字画笔

RenderPercentBox(this.max, this.data);

@override
void performLayout() {
size = constraints.constrain(Size.infinite); //填满
}

@override
void paint(PaintingContext context, Offset offset) {
if (data.isNotEmpty) {
Canvas canvas = context.canvas;
canvas.save(); //保存当前canvas
canvas.translate(offset.dx, offset.dy); //画布移动到当前的便宜位置
double width = size.width / data.length;
for (int i = 0; i < data.length; i++) {
int value = data[i];
bgPaint..color = RandomColor.getColor();
double topHeight = size.height * (value / max);
Rect topRect = Rect.fromLTWH(0, 0, width, topHeight);
canvas.drawRect(topRect, bgPaint);
textPainter
..text = TextSpan(text: value.toString()) //设置文字
..layout(maxWidth: width) //布局
..paint(
canvas,
Offset(
topRect.center.dx - textPainter.width / 2,
topRect.center.dy - textPainter.height / 2,
),
); //绘制
Rect bottomRect =
Rect.fromLTWH(0, topHeight, width, size.height - topHeight);
bgPaint..color = RandomColor.getColor();
canvas.drawRect(bottomRect, bgPaint);
textPainter
..text = TextSpan(text: (max - value).toString())
..layout(maxWidth: width)
..paint(
canvas,
Offset(
bottomRect.center.dx - textPainter.width / 2,
bottomRect.center.dy - textPainter.height / 2,
),
);
canvas.translate(width, 0); //移动画布
}
canvas.restore(); //恢复canvas
}
}
}

///层叠box
class StackBoxWidget extends LeafRenderObjectWidget {
final int boxCount;

const StackBoxWidget({this.boxCount = 7})
: assert(boxCount != null && boxCount > 0);

@override
RenderStackBox createRenderObject(BuildContext context) {
return RenderStackBox(boxCount);
}

@override
void updateRenderObject(
BuildContext context, covariant RenderStackBox renderStackBox) {
renderStackBox.boxCount = boxCount;
}
}

class RenderStackBox extends RenderBox {
int boxCount;
final Paint boxPaint = Paint()..isAntiAlias = true;

RenderStackBox(this.boxCount);

@override
void performLayout() {
size = constraints.constrain(Size.infinite); //填满
}

@override
void paint(PaintingContext context, Offset offset) {
double width = size.width / ((boxCount + 1) / 2);
double halfWidth = width / 2;
Canvas canvas = context.canvas;
canvas.save();
canvas.translate(offset.dx, offset.dy);
double ltrLeft = 0; //左上角开始的方块的left
double top = 0;
double rtlLeft = size.width - width; //右上角开始的方块的left
for (int i = 0; i < boxCount; i++) {
boxPaint.color = RandomColor.getColor();
canvas.drawRect(
Rect.fromLTWH(ltrLeft, top, width, width), boxPaint); //左上角开始的方块
boxPaint.color = RandomColor.getColor();
canvas.drawRect(
Rect.fromLTWH(rtlLeft, top, width, width), boxPaint); //右上角开始的方块
ltrLeft += halfWidth;
rtlLeft -= halfWidth;
top += halfWidth;
}
canvas.restore();
}
}