Knockout - is it possible to combine standard select bindings with a custom binding?

Answer 1

The generic solution

HTML

<select id="parentArea" data-bind="comboBox:{ options: parentAreas, optionsCaption:'Choose...' , optionsText: 'Label', value: selectedParentArea }"></select>

and javascript is

   ko.bindingHandlers.comboBox = {

    init: function (element, valueAccessor, allBindingsAccessor, viewModel, context) {
        var bindings = valueAccessor();
        var optionsObservableArray = bindings.options;
        optionsObservableArray.subscribe(function (newObservableArray) {

            if (newObservableArray && newObservableArray.length > 0) {

                if (element.comboBoxInitialised) {
                    return;
                }

                ko.applyBindingsToNode(element, {
                    options: bindings.options,
                    optionsCaption: bindings.optionsCaption,
                    optionsText: bindings.optionsText,
                    value: bindings.value
                });
                $(element).chosen({});
                element.comboBoxInitialised = true;
            }
        });
    }
};