I have the requirement to show a WARNING POPUP / confirmation box based on a condition. If user edits the opportunity and changes the status to "Closed Won", then clicks on save then depending on whether there are open agreements(Agreement object is child of opp) the user should be shown a warning popup whether they still want to continue. If they click "OK" then the save should happen else it should return to opp or remain on the edit page.
So i found that the save button cannot be overridden. I have tried the following approach.
Thanks in advance. Any approaches are welcome.