The code uses three functions:
SHA-1 digest
MessageDigest md = MessageDigest.getInstance("SHA-1"); byte[] digest = md.digest(text.getBytes("UTF-8"));
Base 64
String base64 = android.util.Base64.encodeToString(digest)
Hex
Use a function like this: http://vinnysoft.blogspot.de/2010/11/code-snippet-to-convert-string-to-hex.html
In summary the last step is totally unnecessary and only blows up the data. The result of base64 is already a printable ASCII String.
Furthermore hashing a password using SHA-1 can be insecure depending what you do with the result. Usually password hashing should always incorporate salting.