Show signature users

app/src/main/java/eu/faircode/email/FragmentMessages.java

@@ -4777,11 +4777,20 @@ public class FragmentMessages extends FragmentBase implements SharedPreferences.
                             int sresult = (sigResult == null ? RESULT_NO_SIGNATURE : sigResult.getResult());
                             if (sresult == RESULT_NO_SIGNATURE)
                                 Snackbar.make(view, R.string.title_signature_none, Snackbar.LENGTH_LONG).show();
-                            else if (sresult == RESULT_VALID_KEY_CONFIRMED)
-                                Snackbar.make(view, R.string.title_signature_valid, Snackbar.LENGTH_LONG).show();
-                            else if (sresult == RESULT_VALID_KEY_UNCONFIRMED)
-                                Snackbar.make(view, R.string.title_signature_unconfirmed, Snackbar.LENGTH_LONG).show();
+                            else if (sresult == RESULT_VALID_KEY_CONFIRMED || sresult == RESULT_VALID_KEY_UNCONFIRMED) {
+                                List<String> users = sigResult.getConfirmedUserIds();
+                                String text;
+                                if (users.size() > 0)
+                                    text = getString(sresult == RESULT_VALID_KEY_UNCONFIRMED
+                                                    ? R.string.title_signature_unconfirmed_from
+                                                    : R.string.title_signature_valid_from,
+                                            TextUtils.join(", ", users));
                                 else
+                                    text = getString(sresult == RESULT_VALID_KEY_UNCONFIRMED
+                                            ? R.string.title_signature_unconfirmed
+                                            : R.string.title_signature_valid);
+                                Snackbar.make(view, text, Snackbar.LENGTH_LONG).show();
+                            } else
                                 Snackbar.make(view, R.string.title_signature_invalid, Snackbar.LENGTH_LONG).show();
 
                             break;

app/src/main/res/values/strings.xml

@@ -802,7 +802,9 @@
 
     <string name="title_signature_none">Message not signed</string>
     <string name="title_signature_valid">Message signature valid</string>
+    <string name="title_signature_valid_from">Message signature valid: %1$s</string>
     <string name="title_signature_unconfirmed">Message signature valid but not confirmed</string>
+    <string name="title_signature_unconfirmed_from">Message signature valid but not confirmed: %1$s</string>
     <string name="title_signature_invalid">Message signature invalid</string>
     <string name="title_signature_invalid_reason">Message signature invalid: %1$s</string>
     <string name="title_signature_certificate_invalid">Certificate chain invalid</string>