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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:math' as math;
import 'package:flutter/material.dart';
import '../rendering/src/sector_layout.dart';
RenderBoxToRenderSectorAdapter initCircle() {
return RenderBoxToRenderSectorAdapter(
innerRadius: 25.0,
child: RenderSectorRing(),
);
}
class SectorApp extends StatefulWidget {
const SectorApp({super.key});
@override
SectorAppState createState() => SectorAppState();
}
class SectorAppState extends State<SectorApp> {
final RenderBoxToRenderSectorAdapter sectors = initCircle();
final math.Random rand = math.Random(1);
List<double> wantedSectorSizes = <double>[];
List<double> actualSectorSizes = <double>[];
double get currentTheta => wantedSectorSizes.fold<double>(0.0, (double total, double value) => total + value);
void addSector() {
final double currentTheta = this.currentTheta;
if (currentTheta < kTwoPi) {
double deltaTheta;
if (currentTheta >= kTwoPi - (math.pi * 0.2 + 0.05))
deltaTheta = kTwoPi - currentTheta;
else
deltaTheta = math.pi * rand.nextDouble() / 5.0 + 0.05;
wantedSectorSizes.add(deltaTheta);
updateEnabledState();
}
}
void removeSector() {
if (wantedSectorSizes.isNotEmpty) {
wantedSectorSizes.removeLast();
updateEnabledState();
}
}
void doUpdates() {
int index = 0;
while (index < actualSectorSizes.length && index < wantedSectorSizes.length && actualSectorSizes[index] == wantedSectorSizes[index])
index += 1;
final RenderSectorRing ring = sectors.child! as RenderSectorRing;
while (index < actualSectorSizes.length) {
ring.remove(ring.lastChild!);
actualSectorSizes.removeLast();
}
while (index < wantedSectorSizes.length) {
final Color color = Color(((0xFF << 24) + rand.nextInt(0xFFFFFF)) | 0x808080);
ring.add(RenderSolidColor(color, desiredDeltaTheta: wantedSectorSizes[index]));
actualSectorSizes.add(wantedSectorSizes[index]);
index += 1;
}
}
static RenderBoxToRenderSectorAdapter initSector(Color color) {
final RenderSectorRing ring = RenderSectorRing(padding: 1.0);
ring.add(RenderSolidColor(const Color(0xFF909090), desiredDeltaTheta: kTwoPi * 0.15));
ring.add(RenderSolidColor(const Color(0xFF909090), desiredDeltaTheta: kTwoPi * 0.15));
ring.add(RenderSolidColor(color, desiredDeltaTheta: kTwoPi * 0.2));
return RenderBoxToRenderSectorAdapter(
innerRadius: 5.0,
child: ring,
);
}
RenderBoxToRenderSectorAdapter sectorAddIcon = initSector(const Color(0xFF00DD00));
RenderBoxToRenderSectorAdapter sectorRemoveIcon = initSector(const Color(0xFFDD0000));
bool _enabledAdd = true;
bool _enabledRemove = false;
void updateEnabledState() {
setState(() {
_enabledAdd = currentTheta < kTwoPi;
_enabledRemove = wantedSectorSizes.isNotEmpty;
});
}
void recursivelyDisposeChildren(RenderObject parent) {
parent.visitChildren((RenderObject child) {
recursivelyDisposeChildren(child);
child.dispose();
});
}
Widget buildBody() {
return Column(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Container(
padding: const EdgeInsets.symmetric(horizontal: 8.0, vertical: 25.0),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceAround,
children: <Widget>[
ElevatedButton(
onPressed: _enabledAdd ? addSector : null,
child: IntrinsicWidth(
child: Row(
children: <Widget>[
Container(
padding: const EdgeInsets.all(4.0),
margin: const EdgeInsets.only(right: 10.0),
child: WidgetToRenderBoxAdapter(
renderBox: sectorAddIcon,
onUnmount: () {
recursivelyDisposeChildren(sectorAddIcon);
},
),
),
const Text('ADD SECTOR'),
],
),
),
),
ElevatedButton(
onPressed: _enabledRemove ? removeSector : null,
child: IntrinsicWidth(
child: Row(
children: <Widget>[
Container(
padding: const EdgeInsets.all(4.0),
margin: const EdgeInsets.only(right: 10.0),
child: WidgetToRenderBoxAdapter(
renderBox: sectorRemoveIcon,
onUnmount: () {
recursivelyDisposeChildren(sectorRemoveIcon);
},
),
),
const Text('REMOVE SECTOR'),
],
),
),
),
],
),
),
Expanded(
child: Container(
margin: const EdgeInsets.all(8.0),
decoration: BoxDecoration(
border: Border.all(),
),
padding: const EdgeInsets.all(8.0),
child: WidgetToRenderBoxAdapter(
renderBox: sectors,
onBuild: doUpdates,
onUnmount: () {
recursivelyDisposeChildren(sectors);
},
),
),
),
],
);
}
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.light(),
title: 'Sector Layout',
home: Scaffold(
appBar: AppBar(
title: const Text('Sector Layout in a Widget Tree'),
),
body: buildBody(),
),
);
}
}
void main() {
runApp(const SectorApp());
}