Data loss warning - Concepts?

Hi,

we develop a SAPUI5 master/detail application which implements navigation via the component / router concept. We use oData models for data handling.

Now we are trying to implement a data loss popup. That means if the model has pending changes, (User has changed data in detail view) we wanna stop navigation a bring up a MessageBox.

With method hasPendingChanges( ) we get the information if changes are made.

With attachRouteMatched( ) on router we can get a event wenn routing has occured.

Problem: How can we prevent a navigation before it really happens? I dont want to implement a check on every Click Event which could navigate. I think it would be nice if we have one event on the router which is called before navigation so that we can react there.

Someone an idea?

Best regards

Richard Brünning