Save form only when field is selected

Forms
1

Dear all,

when saving, a popup message should appear if a field was not selected. Can you give me an example.

Best wishes
Tom

2

Dear @TWendt,
What type of a field is it? Most types of fields can just be made required:
image

3

Dear Nikita,

it is a Yes/No field.

Best wishes
Tom

4

Dear @TWendt,
If you don't want to set it as required in SharePoint List settings, you can always use JavaScript:

fd.spRendered(function(){
  fd.field('Toggle').required = true; 
});
5

Dear Nikita,

when the user press Save und the box Entries complete are not marked, I need a popup window with a message "If all entries are correct, check the box Entries complete and then press Save".

Best wishes
Tom

6

Dear @TWendt,
You can try a custom validator, will this work for you?

fd.spRendered(function () {
    fd.field('Toggle').addValidator({
        name: 'Yes/No validator',
        error: 'If all entries are correct, check the box Entries complete and then press Save',
        validate:function(value){
            if(!value){
                return false;
            }
            return true;
        }
    });
});