unmount sdcard programmatically in Android?

1. I 开发者_StackOverflow中文版am working to implement Mount/Unmount sdcard support in my Android application, Am able to get sdcard state by Environment.getExternalStorageState().I know we can call Settings Intent and Mount/Unmount, but my requirement has to do programmatically with out calling Settings Intent.
2. Is it possible to Enable/Disable the Settings application in Android?

The settings app uses this permission <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /> See if you can use it.