Can't create a directory on /storage/emulated/0 on emulator

问题

I'm trying to create a directory on my android emulator but I can't do it, I already have the permission on manifest write_storage, and I get no erros but mkdir() return false, I verify if external storage is writtable too and it is, it works on physical devices my code:

 /// Cria uma nova pasta para colocar o backup
    File direct = new File(Environment.getExternalStorageDirectory(),
            "/Financas RW Backup");
    try {


        if (!direct.exists()) {
            if(isExternalStorageWritable()&&isExternalStorageReadable()) {
              if(  direct.mkdir()) {
                  fachada.showMessage(ExportImportDB.this," Criado");
              }else{
                  fachada.showMessage(ExportImportDB.this," Não Criado");
              }
            }
        }
    } catch (Exception e) {
        fachada.showMessage(this, e.toString());
    }

回答1:

You have to options:

• Downgrade your compileSdkVersion and targetSdkVersion to lower version in your build.gradle
• Request write permission at runtime is required on Android 6 .

I personally don't advice the first one. For more info check:

• Android 6.0 Marshmallow. Cannot write to SD Card
• Google Play services 8.1 and Android 6.0 Permissions

Hope this helps!!

回答2:

I had a similar issue was fixed by using mkdirs instead of mkdir

来源：https://stackoverflow.com/questions/36084959/cant-create-a-directory-on-storage-emulated-0-on-emulator