Convert file: Uri to File in Android

What you want is…

new File(uri.getPath());

… and not…

new File(uri.toString());

Notes

1. For an android.net.Uri object which is named uri and created exactly as in the question, uri.toString() returns a String in the format "file:///mnt/sdcard/myPicture.jpg", whereas uri.getPath() returns a String in the format "/mnt/sdcard/myPicture.jpg".
2. I understand that there are nuances to file storage in Android. My intention in this answer is to answer exactly what the questioner asked and not to get into the nuances.