使用Kotlin创建一个新的目录，Mkdir（）不起作用

var filename = "blesson.txt" var wallpaperDirectory = File("/sdcard/Wallpaper") wallpaperDirectory.mkdirs() val outputFile = File(wallpaperDirectory, filename) val fos = FileOutputStream(outputFile) 

我正在尝试使用Kotlin在Android设备上创建一个新的目录，但函数mkdirs()不起作用。

 var filename = "blesson.txt" var wallpaperDirectory = File(Environment.getExternalStorageDirectory().absolutePath)//("/sdcard/Wallpaper") wall val outputFile = File(wallpaperDirectory, filename) val fos = FileOutputStream(outputFile) 

我也尝试了这一点，它不是一个新的目录任何帮助是值得欢迎的

Answer 1

这在Kotlin上完美运行

 class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) var filename = "blesson.txt" // create a File object for the parent directory val wallpaperDirectory = File("/sdcard/Wallpaper/") // have the object build the directory structure, if needed. wallpaperDirectory.mkdirs() // create a File object for the output file val outputFile = File(wallpaperDirectory, filename) // now attach the OutputStream to the file object, instead of a String representation try { val fos = FileOutputStream(outputFile) } catch (e: FileNotFoundException) { e.printStackTrace() } } }