Android - Get hash key for Facebook app

get-hash-key-for-facebook-app.txt

General command:
keytool -exportcert -alias [your-key-alias] -keystore [/path/to/your/file.keystore] | openssl sha1 -binary | openssl base64

Example:
On OS X, run:
keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | openssl sha1 -binary | openssl base64
On Windows, run:
keytool -exportcert -alias androiddebugkey -keystore %HOMEPATH%\.android\debug.keystore | openssl sha1 -binary | openssl
base64

You can also manually modify the sample code to use the right key hash. For example in HelloFacebookSampleActivity class make a temporary change to the onCreate():
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    
    // Add code to print out the key hash
    try {
        PackageInfo info = getPackageManager().getPackageInfo(
                "com.facebook.samples.hellofacebook", 
                PackageManager.GET_SIGNATURES);
        for (Signature signature : info.signatures) {
            MessageDigest md = MessageDigest.getInstance("SHA");
            md.update(signature.toByteArray());
            Log.d("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT));
            }
    } catch (NameNotFoundException e) {
        
    } catch (NoSuchAlgorithmException e) {
        
    }
    
    ...