knockoutjs(03) ko + jquery ui

<h1 class="header" data-bind="text: label"></h1>

<div id="dialog" data-bind="dialog: {autoOpen: false, title: 'Dialog test' }, dialogVisible: isOpen">foo dialog</div>

<div>
    <button data-bind="click: open">Open</button>
    <button data-bind="click: close" >Close</button>
</div>

<hr/>

<div data-bind="text: ko.toJSON($root)"></div>

ko.bindingHandlers.dialog = {
        init: function(element, valueAccessor, allBindingsAccessor) {
            var options = ko.utils.unwrapObservable(valueAccessor()) || {};
            //do in a setTimeout, so the applyBindings doesn't bind twice from element being copied and moved to bottom
            setTimeout(function() { 
                options.close = function() {
                    allBindingsAccessor().dialogVisible(false);                        
                };
                
                $(element).dialog(options);          
            }, 0);
            
            //handle disposal (not strictly necessary in this scenario)
             ko.utils.domNodeDisposal.addDisposeCallback(element, function() {
                 $(element).dialog("destroy");
             });   
        },
        update: function(element, valueAccessor, allBindingsAccessor) {
             var shouldBeOpen = ko.utils.unwrapObservable(allBindingsAccessor().dialogVisible);
             $(element).dialog(shouldBeOpen ? "open" : "close");
             
        }
};
    

var viewModel = {
    label: ko.observable('dialog test'),
    isOpen: ko.observable(false),
    open: function() {
       this.isOpen(true);   
    },
    close: function() {
       this.isOpen(false);   
    }
};

ko.applyBindings(viewModel);
        

.header {
    font-size: 16px;
    font-family: sans-serif;
    font-weight: bold;
    margin-bottom: 20px;
}

http://jsfiddle.net/rniemeyer/SnPdE/