How to validate a drop-down list before move on?

[Former Community Member]

Hello,

I want to force the user to select a value in the drop-down list before she can move on the the next  field.  for instances, I have a drop-down list A, whose default value is empty.  as the user clicks on the next field, I need to throw a warning that she needs to select the value for drop-down list A.

Thank you for your help.

[dohanlon]

On the exit event of the drop-down list, you can do a test

if ( this.isNull )
{
    xfa.host.messageBox("Select item from list");
}

You can place any other custom changes to the field inside the if statement to show the error.

[Former Community Member]

Hi,

Thank you.  It looks like this only validate when I click on the field without entering/selecting then move on.  Is there a way I can validate the field in a way that if I have field 1/dropdown1, then field 2/dropdown 2.  If I click on field 2, there is a message popup saying that 'field 1/dropdown 1 can't be empty.  Please make your selection before move on'.

Thanks.

[dohanlon · Accepted solution]

Yeah it would be the same idea basically. But you just need to decide where to have the event (on enter/ on exit of which field) and then use the same code where you can as many conditions as you like. For example,

if ( field1.isNull && dropdown1.isNull )

{

...

}

and so on.

[Former Community Member]

Ah, I see. Thank you.  got it working now.