knockout.jsでdatetimepickerの 'required'バインディングを動的に変更できますか？

Question

私はビューモデルのmodel.statusプロパティに応じて必要なdatetimepickerを持っています。どうすればこれを受け取ることができますか？ここで

<div class='input-group date' data-bind="dateTimePicker: model.dateClaimClosed, dateTimePickerOptions: { required: lookUpViewValue(model.status) == 'Closed' }"> 
    <input type='text' class="form-control submittable" id="dateClaimClosed" name="dateClaimClosed" placeholder="Select date..." /> 
    <span class="input-group-addon"><span class="glyphicon glyphicon-calendar"></span> 
</div> 

は私bindingHandlerです：

ko.bindingHandlers.dateTimePicker = { 
     init: function (element, valueAccessor, allBindingsAccessor) { 

      var options = {}; 

      options.format = "DD/MM/YYYY"; 

      $(element).datetimepicker(options); 

      ko.utils.registerEventHandler(element, "dp.change", function (event) { 
       var value = valueAccessor(); 
       if (ko.isObservable(value)) { 

        if (event.date != null && !(event.date instanceof Date)) { 

         value(event.date != false ? event.date.toDate() : ""); 
        } else { 

         value(event.date); 
        } 
       } 
      }); 

      ko.utils.domNodeDisposal.addDisposeCallback(element, function() { 
       var picker = $(element).data("DateTimePicker"); 
       if (picker) { 
        picker.destroy(); 
       } 
      }); 
     }, 
     update: function (element, valueAccessor, allBindings, viewModel, bindingContext) { 

      var options = allBindings().dateTimePickerOptions || {}; 
      var required = options.required || false;   

      valueAccessor().extend({ required: required }); 
      ko.bindingHandlers.value.update(element, valueAccessor); 

      var picker = $(element).data("DateTimePicker"); 
      if (picker) { 
       var koDate = ko.utils.unwrapObservable(valueAccessor()); 

       if (koDate === undefined) 
        koDate = null; 
       else 
        koDate = (typeof (koDate) !== 'object') ? moment(koDate) : koDate; 

       picker.date(koDate); 
      } 
     } 
    }; 

Answer 1

見つかりソリューション：

if (required) 
    valueAccessor().extend({ required: required }); 
else 
    valueAccessor().rules.remove(function (item) { 
     return item.rule == "required"; 
    });