Replace empty buttonLabel with 'OK'
diff --git a/www/notification.js b/www/notification.js
index 751f4ce..b6d4d39 100644
--- a/www/notification.js
+++ b/www/notification.js
@@ -39,7 +39,7 @@
alert: function(message, completeCallback, title, buttonLabel) {
var _message = (typeof message === "string" ? message : JSON.stringify(message));
var _title = (typeof title === "string" ? title : "Alert");
- var _buttonLabel = (typeof buttonLabel === "string" ? buttonLabel : "OK");
+ var _buttonLabel = (buttonLabel && typeof buttonLabel === "string" ? buttonLabel : "OK");
exec(completeCallback, null, "Notification", "alert", [_message, _title, _buttonLabel]);
},