Android Dev

java.security.DigestInputStream

MessageDigest md = MessageDigest.getInstance("MD5");InputStream is = new FileInputStream("file.txt");try {  is = new DigestInputStream(is, md);  // read stream to EOF as normal...}finally {  is.close();}byte[] digest = md.digest();

In my_button we define 4 states (as a button has 4 states: not pressed and not focused, pressed and focused, pressed and not focused, not pressed and focused) with each of those states having their own drawable.