Flutter 的 main.dart 文件在 Android Studio 中执行时卡在“Syncing files to device Android SDK built for x86 64...”

Question

I am trying out my first ever flutter code on Android Studio and I am displaying it on an emulator. I do get the output but the compilation never ends, which means I cannot Hot Restart my code. The tutorial I am learning from isn't getting this problem.

EDIT : Some new errors arose. It started hanging at "Installing build\\app\\outputs\\apk\\app.apk", I solved that issue and now it displays this. It is intermittent, the skipped frame and lines interchange but more or less the problem remains the same. Please help am going crazy over solving it :)

The following code appears:

Launching lib\main.dart on Android SDK built for x86 64 in debug mode...
Running Gradle task 'assembleDebug'...
√ Built build\app\outputs\apk\debug\app-debug.apk.
Syncing files to device Android SDK built for x86 64...
I/Choreographer( 5985): Skipped 61 frames!  The application may be doing too much work on its main thread.
D/EGL_emulation( 5985): eglMakeCurrent: 0x7e7ece03e300: ver 3 0 (tinfo 0x7e7ece1a85e0)
I/OpenGLRenderer( 5985): Davey! duration=1554ms; Flags=1, IntendedVsync=1503595359014, Vsync=1504612025640, OldestInputEvent=9223372036854775807, NewestInputEvent=0, HandleInputStart=1504619561700, AnimationStart=1504619633200, PerformTraversalsStart=1504619653300, DrawStart=1504626010200, SyncQueued=1504626824700, SyncStart=1504630541800, IssueDrawCommandsStart=1504630721200, SwapBuffers=1504690106800, FrameCompleted=1505153649500, DequeueBufferDuration=49170000, QueueBufferDuration=2336000, 
D/EGL_emulation( 5985): eglMakeCurrent: 0x7e7ecc6fa7e0: ver 3 0 (tinfo 0x7e7ecc62baa0)
Syncing files to device Android SDK built for x86 64...

Answer 1

Well, it seems on Linux that's because of some changes in kernel 5.5. I tested multiple times and I am sure - on kernel 5.4 it works, but on kernel 5.5 refactoring hangs and also debug does not work.

That's strange, I have no idea how is is related to kernel (refactoring? wtf?), I can suspect some changes in filsestem handling could cause that? Need to create bug report to InteliJ or Flutter and tell them new kernel causes problem.

Also strange, when developing in Java/Kotlin with Android Studio, I have no problems, refactoring and debug both work just fine. So this must be related to Flutter.

So, on Linux need to downgrade kernel to 5.4 for now (no idea about Mac or Win).

Answer 2

Put this statement right after the beginning of main function.

WidgetsFlutterBinding.ensureInitialized();

And then restart the application.

Answer 3

当我没有连接到网络时，我遇到了这个问题。我是第一次运行那个项目。所以检查你的互联网并重新启动应用程序几次，它会运行得很快

Answer 4

I have an exactly same issue on linux5.5 kernel.

inxi

CPU: Quad Core AMD Ryzen 3 PRO 3300U w/ Radeon Vega Mobile Gfx (-MCP-) 
speed/max: 1397/1400 MHz Kernel: 5.5.2-1-MANJARO x86_64 Up: 1d 4h 05m 
Mem: 12541.8/22014.1 MiB (57.0%) Storage: 476.94 GiB (15.3% used) Procs: 332 
Shell: fish 3.0.2 inxi: 3.0.37

flutter doctor

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, v1.12.13+hotfix.8, on Linux, locale en_US.UTF-8)

[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] Android Studio (version 3.5)
[✓] Connected device (1 available)

• No issues found!

Answer 5

Only agreeing with user1209216 .

Using Visual Studio, execution was stuck on "Syncing files to device" while using kernel-5.5.8-200.fc31.

I downgraded to kernel-5.3.7-301.fc31 and was able to launch a Flutter app on an emulator and a physical device.

See also: https://github.com/flutter/flutter/issues/

You can either downgrade to a previous kernel until a new version of Flutter is released on the stable channel or run flutter channel master .

More information on how Flutter structures their release channels: https://github.com/flutter/flutter/wiki/Flutter-build-release-channels

Answer 6

I was facing the same error in my Fedora which is running on the Linux kernel (5.11). I tried several things but nothing worked. It was taking 2-3 forced restart to finish the build.

I downgraded the emulator API from API level 30 (x86) to API level 28 (x86_64) now it is working seamlessly on my machine. Build of a small app only takes 1 minute or so. If nothing worked for you, therefore, you may try downgrading the API level of the emulator.

Answer 7

I had the same situation today, and took me a few hours to find out the solution, and it was very simple.

I basically started building a loop, then got distracted with something else, and forgot to delete it.

So what caused my "Syncing files to device" not to finish, and my initial page to freeze, was this. I had an infinite loop in my Home initState.