在VS代码中构建我的flutter应用程序后，我成功地运行了应用程序，一切正常。但是在应用程序重新启动2次或更多次之后，每当我再次运行代码时，构建就会失败。这是弹出的错误。

Target debug_android_application failed: FileSystemException: Cannot copy file to 'J:\flutter_projects\webdoc\build\app\intermediates\flutter\debug\flutter_assets\assets\images\background.png', path = 'J:\flutter_projects\webdoc\assets\images\background.png' (OS Error: Access is denied.
, errno = 5)
build failed.

FAILURE: Build failed with an exception.

* Where:
Script 'C:\src\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 780

* What went wrong:
Execution failed for task ':app:compileFlutterBuildDebug'.
> Process 'command 'C:\src\flutter\bin\flutter.bat'' finished with non-zero exit value 1

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 9s
Running Gradle task 'assembleDebug'...
Running Gradle task 'assembleDebug'... Done                        10.2s
Gradle task assembleDebug failed with exit code 1

当第一次出现此错误时，我从当前目录中删除所有文件并复制到其他目录中，然后它再次正常工作。但即使是现在运行2或3次后再次弹出错误。是否有任何可用的修复此问题？

我试着删除.vscode，再次重建，但仍然是一样的！！