Improve documentation for UI classes

src/qt/askpassphrasedialog.h

@@ -9,16 +9,18 @@ namespace Ui {
 
 class WalletModel;
 
+/** Multifunctional dialog to ask for passphrases. Used for encryption, unlocking, and changing the passphrase.
+ */
 class AskPassphraseDialog : public QDialog
 {
     Q_OBJECT
 
 public:
     enum Mode {
-        Encrypt,    // Ask passphrase x2
-        Unlock,     // Ask passphrase
-        ChangePass, // Ask old passphrase + new passphrase x2
-        Decrypt   // Ask passphrase
+        Encrypt,    /**< Ask passphrase twice and encrypt */
+        Unlock,     /**< Ask passphrase and unlock */
+        ChangePass, /**< Ask old passphrase + new passphrase twice */
+        Decrypt     /**< Ask passphrase and decrypt wallet */
     };
 
     explicit AskPassphraseDialog(Mode mode, QWidget *parent = 0);