dynamic binding in CoffeeKup

Question

I am writing an app with node.js and coffee-script and coffeekup as template engine. I have a form where I'd like to enable or disable a button depending on whether there are values in some input fields. I am wondering whether there is a straightforward mechanism like in Sproutcore or Ember, where just a binding will do. How should I go about it?

Answer 1

No, there is no such binding out of the box. You have to either implement something like Ember, Knockout or Serenade.js, or roll it yourself. If it's just this one form, I would just have a small script (jQuery below):

function validateForm() {
  // Check if form fields are valid, return true if valid, false if not.
}

// Update the disabled attribute on a button inside "formId" anytime an input field is changed.
$("#formId").on("change", "input", function(event) {
  $("#formId button").attr("disabled", !validateForm());
});