function() {
        // Get the current value of the property
        newClass = this._classStringForProperty(binding);
        elem = this.$();

        // If we had previously added a class to the element, remove it.
        if (oldClass) {
          elem.removeClass(oldClass);
          // Also remove from classNames so that if the view gets rerendered,
          // the class doesn't get added back to the DOM.
          classNames.removeObject(oldClass);
        }

        // If necessary, add a new class. Make sure we keep track of it so
        // it can be removed in the future.
        if (newClass) {
          elem.addClass(newClass);
          oldClass = newClass;
        } else {
          oldClass = null;
        }
      }
function() {
        // Get the current value of the property
        newClass = this._classStringForProperty(binding);
        elem = this.$();

        // If we had previously added a class to the element, remove it.
        if (oldClass) {
          elem.removeClass(oldClass);
          // Also remove from classNames so that if the view gets rerendered,
          // the class doesn't get added back to the DOM.
          classNames.removeObject(oldClass);
        }

        // If necessary, add a new class. Make sure we keep track of it so
        // it can be removed in the future.
        if (newClass) {
          elem.addClass(newClass);
          oldClass = newClass;
        } else {
          oldClass = null;
        }
      }
function ( ) { // Get the current value of the property newClass = this . _classStringForProperty ( binding ) ; elem = this . $ ( ) ; // If we had previously added a class to the element, remove it. if ( oldClass ) { elem . removeClass ( oldClass ) ; // Also remove from classNames so that if the view gets rerendered, // the class doesn't get added back to the DOM. classNames . removeObject ( oldClass ) ; } // If necessary, add a new class. Make sure we keep track of it so // it can be removed in the future. if ( newClass ) { elem . addClass ( newClass ) ; oldClass = newClass ; } else { oldClass = null ; } }
Set up an observer on the context. If the property changes, toggle the class name.
Set up an observer on the context . If the property changes toggle the class name .