ClassNamesSupport#classNameBindings

A list of properties of the view to apply as class names. If the property is a string value, the value of that string will be applied as a class name.

// Applies the 'high' class to the view element
Ember.View.extend({
  classNameBindings: ['priority'],
  priority: 'high'
});

If the value of the property is a Boolean, the name of that property is added as a dasherized class name.

// Applies the 'is-urgent' class to the view element
Ember.View.extend({
  classNameBindings: ['isUrgent'],
  isUrgent: true
});

If you would prefer to use a custom value instead of the dasherized property name, you can pass a binding like this:

// Applies the 'urgent' class to the view element
Ember.View.extend({
  classNameBindings: ['isUrgent:urgent'],
  isUrgent: true
});

This list of properties is inherited from the view's superclasses as well.