Flutter Hot Reload not working (Windows 10 / Android Emulator / VS Code)

[LyalinDotCom]

Steps to Reproduce

1. Created new sample app, add some text widget
2. Run the app on android emulator, app appears
3. Make change to app but nothing happens after saving
4. restart app and changes appear.

This was working fine yesterday and now its not. I even rebuilt the emulator again to make sure that wasnt the issue. Glad to provide any logs that can help if below is not enough.

Logs

!! PLEASE REVIEW THIS LOG FOR SENSITIVE INFORMATION BEFORE SHARING !!

Dart Code extension: 3.7.1
Flutter extension: 3.7.1 (not activated)
VS Code: 1.41.1
Platform: win
Workspace type: Flutter
Multi-root?: false
Dart SDK:
Loc: C:\src\flutter\bin\cache\dart-sdk
Ver: 2.7.0-dev.2.1
Flutter SDK:
Loc: C:\src\flutter
Ver: 1.12.13+hotfix.7
HTTP_PROXY: undefined
NO_PROXY: undefined

Wed Jan 29 2020 [14:51:01 GMT-0800 (Pacific Standard Time)] Log file started
[2:51:10 PM] [FlutterRun] [Info] [Flutter] ==> [{"id":"12","method":"app.restart","params":{"appId":"8b811d64-b936-4745-b5c6-4d9f23747cfb","fullRestart":false,"pause":true,"reason":"save"}}]
[2:51:10 PM] [FlutterRun] [Info] [Flutter] <== [{"event":"app.progress","params":{"appId":"8b811d64-b936-4745-b5c6-4d9f23747cfb","id":"13","progressId":"hot.reload","message":"Performing hot reload..."}}]
[2:51:10 PM] [FlutterRun] [Info] [Flutter] <== [{"event":"app.progress","params":{"appId":"8b811d64-b936-4745-b5c6-4d9f23747cfb","id":"14","progressId":null,"message":"Syncing files to device AOSP on IA Emulator..."}}]
[2:51:10 PM] [FlutterRun] [Info] [Flutter] <== [{"event":"app.progress","params":{"appId":"8b811d64-b936-4745-b5c6-4d9f23747cfb","id":"14","progressId":null,"finished":true}}]
[2:51:10 PM] [Observatory] [Info] [Flutter] <== {"jsonrpc":"2.0","method":"streamNotify","params":{"streamId":"Isolate","event":{"type":"Event","kind":"IsolateReload","isolate":{"type":"@isolate","id":"isolates/1865803559515751","name":"main","number":"1865803559515751"},"timestamp":1580338270018,"status":"success"}}}
[2:51:10 PM] [Observatory] [Info] [Flutter] <== {"jsonrpc":"2.0","method":"streamNotify","params":{"streamId":"Debug","event":{"type":"Event","kind":"PausePostRequest","isolate":{"type":"@isolate","id":"isolates/1865803559515751","name":"main","number":"1865803559515751"},"timestamp":1580338270020}}}
[2:51:10 PM] [Observatory] [Info] [Flutter] ==> {"id":"969","method":"resume","params":{"isolateId":"isolates/1865803559515751"}}
[2:51:10 PM] [Observatory] [Info] [Flutter] <== {"jsonrpc":"2.0", "result":{"type":"Success"},"id":"969"}
[2:51:10 PM] [Observatory] [Info] [Flutter] <== {"jsonrpc":"2.0","method":"streamNotify","params":{"streamId":"Debug","event":{"type":"Event","kind":"Resume","isolate":{"type":"@isolate","id":"isolates/1865803559515751","name":"main","number":"1865803559515751"},"timestamp":1580338270029}}}
[2:51:10 PM] [FlutterRun] [Info] [Flutter] <== [{"event":"app.progress","params":{"appId":"8b811d64-b936-4745-b5c6-4d9f23747cfb","id":"13","progressId":"hot.reload","finished":true}}]
[2:51:10 PM] [FlutterRun] [Info] [Flutter] <== Reloaded 1 of 478 libraries in 191ms.
[2:51:10 PM] [FlutterRun] [Info] [Flutter] <== [{"id":"12","result":{"code":0,"message":"Reloaded 1 of 478 libraries"}}]
[2:51:10 PM] [Observatory] [Info] [Flutter] <== {"jsonrpc":"2.0","method":"streamNotify","params":{"streamId":"Extension","event":{"type":"Event","kind":"Extension","extensionKind":"Flutter.Frame","isolate":{"type":"@isolate","id":"isolates/1865803559515751","name":"main","number":"1865803559515751"},"timestamp":1580338270197,"extensionData":{"number":3,"startTime":1169721085,"elapsed":8470,"build":5292,"raster":2231}}}}
Wed Jan 29 2020 [14:51:23 GMT-0800 (Pacific Standard Time)] Log file ended

Flutter Doctor

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.12.13+hotfix.7, on Microsoft Windows [Version 10.0.18363.592], locale en-US)

[√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[√] Android Studio (version 3.5)
[√] VS Code (version 1.41.1)
[√] VS Code, 64-bit edition (version 1.37.0)
[√] Connected device (1 available)

• No issues found!

[LyalinDotCom]

Update: I continued working with the same app project through the tutorial i am looking at and just used manual restart button to keep me going. Eventually when i added a new .dart file to hold some of my views hot reload just started to work all of a sudden

[jonahwilliams]

Make change to app but nothing happens after saving

You'll have to be more specific here, did you change it in such a way that you hit a limitation documented in https://flutter.dev/docs/development/tools/hot-reload ?

[LyalinDotCom]

No, this was all very vanilla, just going through a pluralsight tutorial, hello world type modules. Hot reload stopped working through morning and just started working after I refactored app. I looked at your docs the best i could and i see no reason for the stop or start. I know this isn't very helpful...

do the logs help at all above or nothing strange there? they were taken at the time when hot reload stopped working.

For the last hour now its been fine and im on a new app for a new module (all apps created from scratch via flutter new app command)

[jonahwilliams]

Nothing in the logs shows that something is off. I see "reloaded 1 of X" libraries response, which leads me to believe it was updating fine but maybe not in a hot reloadable way?

We've definitely thought about ways to make these scenarios easier to identify. For example, the vm can return coverage information that could tell us if a line of code had re-run after a reload. That might indicate the app is structured in such a way that reloads don't work.

That is just sort of a guess though, I don't know for sure

[jonahwilliams]

When you were making the changes, can you confirm that you were seeing the "Reload N of X libraries" message?

Also, if you don't mind could you link the pluralsight tutorial? I could try to follow along to see if I can repro.

[DiyaaKathim]

when you use widget from another .dart file maybe for some reason flutter import your .dart like
import file:///C:/Users/.../.../< App Name >/lib/filename.dart
when that happened the hot reload and hot restart will not work for that .dart file and to fix that you should use
import package:< App Name >/filename.dart
then stop the app and run again

---

that happen to me today for the first time and that how i fix it

[Dibitybopty]

I'm kicking myself right now. I thought I had this issue too, hot reload suddenly stopped working for me. I just had to hit CTRL-F5 to bring up the flutter menu for it to work again. Hopefully this helps anyone as silly as me. :)

[jmagman]

Without additional information, we are unfortunately not sure how to resolve this issue. We are therefore reluctantly going to close this bug for now. Please don't hesitate to comment on the bug if you have any more information for us; we will reopen it right away!

Thanks for your contribution.

[bonniesimon]

I'm kicking myself right now. I thought I had this issue too, hot reload suddenly stopped working for me. I just had to hit CTRL-F5 to bring up the flutter menu for it to work again. Hopefully this helps anyone as silly as me. :)

I'm using the cli. And I'm experiencing similar problems.
When I press 'r' in the cli, the app reloads. But it doesn't reload after I make changes. I have to manually press 'r' to get the changes to appear.

[Dibitybopty]

I'm using the cli. And I'm experiencing similar problems.
When I press 'r' in the cli, the app reloads. But it doesn't reload after I make changes. I have to manually press 'r' to get the changes to appear.

Hot reload only works in debug mode. You need to run your app in debug mode in an IDE.