Dear All,

Good day to you. I am just started learning SS about 1 month ago and trying to build a simple admin site module for learning purpose.
I am using SS v3.0.5 with CMS. My module layout is look like this:

Marker has relationship with Sub Markers

Below is my problem would like solve it:
1. On submit validation and display error message below the field box
- my current validation is look like this:

Targeted to achieve:

2. Stop deletion action and redirect page to main and display error message if validation not pass (onBeforeDelete function)
This action activated when Marker still has child in Sub Markers. So when I delete the Marker I will check whether there is child in Sub Markers. If yes, then delete method will stop and the page redirect to main and display error message.

For more detail please view script attached.

Appreciate if someone can help me on above problem. Thank you very much. : )