Seeking Help with UI Page Client script

[Still Learning]

Hello Everyone, 

New developer here.  I have a requirement to add an alert message when a choice field selection is made and make work notes mandatory on the UI page.  The field is Validation Type (valtype on the UI page / 'validation_type' on the Form) when the user selects the option: "Accepting Risk/Not Testing" an alert popup message should appear and the work notes field should become mandatory. 

I've written a script in the client script section of the UI page but it is not working.  Can anyone please assist me with this?

Edited to remove code

[SVimes · Accepted solution]

I took what you put together and started looking through what is actually rendered. There is an onchange event already attached to the <select> tag that is rendered on the page simply called onChange. It passes in the name of the ui_choice_input_field so it's easy to determine which input field changed in the function if you have more than one of them.

Using that, I changed the Client Script to the following which worked for the alert part:

function onChange(ui_choice_input_field_name){
	if(jQuery("#" + ui_choice_input_field_name + " option:selected").val() == "not_testing"){
		alert('By selecting Accepting Risk/Not Testing, you will be responsible for any issues with functionality experienced by your CI/Application post release activity. Please update the work notes with the reason you are accepting risk/not testing.');
		field.column_name = "work_notes_update";
		field.mandatory = true;
	}
}

I'm not sure about setting the field you want to Mandatory though since I don't know how the UI Page is accessed/rendered and there isn't a work_notes_update field on the UI Page with what you provided. I hope this gets you started at least.

[Still Learning]

Thank you so much for your help with this script Claude!!! It worked exactly as I needed it to (and I learned what my mistakes were in the process) - thank you so much!!!