CircularProgressIndicator causes 100% CPU on IOS simulator

[mgleason]

Steps to Reproduce

1. Create main.dart containing:

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: CircularProgressIndicator(
          value: .8,
        ),
      ),
    );
  }
}

2. Run it on the IOS simulator
3. Run top -o cpu

PID    COMMAND      %CPU
47633  Runner       58.6
46728  backboardd   43.4

4. Replace CircularProgressIndicator(value: .8), with Column(),

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: Column(),
      ),
    );
  }
}

5. Note Simulator CPU usage drops to zero.

Flutter Doctor

[✓] Flutter (Channel beta, v0.6.0, on Mac OS X 10.13.6 17G65, locale en-US)
    • Flutter version 0.6.0 at /Users/jeff/Dev/2_flutter_tool/flutter
    • Framework revision 9299c02cf7 (3 weeks ago), 2018-08-16 00:35:12 +0200
    • Engine revision e3687f70c7
    • Dart version 2.1.0-dev.0.0.flutter-be6309690f

[✗] Android toolchain - develop for Android devices
    ✗ Unable to locate Android SDK.
      Install Android Studio from: https://developer.android.com/studio/index.html
      On first launch it will assist you in installing the Android SDK components.
      (or visit https://flutter.io/setup/#android-setup for detailed instructions).
      If Android SDK has been installed to a custom location, set $ANDROID_HOME to that location.

[✓] iOS toolchain - develop for iOS devices (Xcode 9.4.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 9.4.1, Build version 9F2000
    • ios-deploy 1.9.2
    • CocoaPods version 1.5.3

[✗] Android Studio (not installed)
    • Android Studio not found; download from https://developer.android.com/studio/index.html
      (or visit https://flutter.io/setup/#android-setup for detailed instructions).

[✓] VS Code (version 1.26.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 2.18.0

[✓] Connected devices (1 available)
    • iPhone 7 • D840D735-FEF3-4486-940C-923FC8044EB5 • ios • iOS 11.4 (simulator)

[kirgene]

I see high CPU usage when running flutter app using desktop-embedding on Ubuntu 18.04.
Here is an endless animation example that demonstrates this issue:
https://gist.github.com/kirgene/00362d280430df48513ee691b2149a9e

[DazChong]

This issue still exist today:

[✓] Flutter (Channel stable, v1.12.13+hotfix.5, on Mac OS X 10.15.2 19C57,
    locale en-SG)
[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
[✓] Xcode - develop for iOS and macOS (Xcode 11.3)
[✓] Android Studio (version 3.5)
[✓] VS Code (version 1.41.0)
[✓] Connected device (2 available)

[magnuswikhog]

This issue affects Android Emulators as well, CPU usage skyrockets and fans go on full blast after showing a CircularProgressIndicator for ~20+ seconds.

[✓] Flutter (Channel stable, v1.9.1+hotfix.6, on Mac OS X 10.14.5 18F132, locale en-SE)
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] Xcode - develop for iOS and macOS (Xcode 10.3)
[✓] Android Studio (version 3.3)
[✓] IntelliJ IDEA Ultimate Edition (version 2018.3.4)
[✓] Connected device (1 available)

[kasvith]

Still exists

[√] Flutter (Channel stable, v1.12.13+hotfix.9, on Microsoft Windows [Version 10.0.18363.720], locale en-US)
[!] Android toolchain - develop for Android devices (Android SDK version 29.0.1)
    X Android license status unknown.
      Try re-installing or updating your Android SDK Manager.
      See https://developer.android.com/studio/#downloads or visit https://flutter.dev/setup/#android-setup for detailed instructions.
[!] Android Studio (version 3.5)
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
[!] IntelliJ IDEA Ultimate Edition (version 2019.2)
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
[√] VS Code (version 1.44.2)
[√] Connected device (1 available)

[retkpop]

Still exists

[treeder]

Still exists, in particular when indeterminate. Why was this closed?

[nicholasspencer]

I experience this regularly.

[treeder]

Also a problem on flutter web, pins the CPU in Chrome. Especially bad when dev tools is open and it looks like it's continuously logging the frame output to debug (hidden logs in dev tools, that you can unhide to see).

[xurshid29]

Still exists

[github-actions]

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.