knockout-sortable - connected lists extension

https://github.com/rniemeyer/knockout-sortable

by Asle Gundersby

HTML

<script src="http://knockoutjs.com/downloads/knockout-2.2.1.js"></script>
<script src="https://rawgithub.com/rniemeyer/knockout-sortable/master/build/knockout-sortable.js"></script>
<div id="main">
    <h3>High Priority</h3>

    <div class="high"
         data-bind="sortable: { template: 'taskTmpl', data: highPriorityTasks, afterMove: myDropCallback }, accordion: {}"></div>

    <h3>Normal Priority</h3>

    <div data-bind="sortable: { template: 'taskTmpl', data: normalPriorityTasks, afterMove: myDropCallback }, accordion: {}"></div>

    <a href="#" data-bind="click: addTask">Add Task</a>
    <hr/>
    <h3>Trash</h3>

    <div class="trash" data-bind="sortable: trash"></div>

    <script id="taskTmpl" type="text/html">
        <div class="item"> 
            <div data-bind="attr: {'id': 'task' + taskID}">  
                <div class="accordion-header ui-widget-header" data-bind="click: $root.selectedItem">
                    <span data-bind="visible: !$root.isTaskSelected($data)">
                        <a href="#" data-bind="text: name, click: $root.selectedTask"></a>
                    </span>
                    <span data-bind="visibleAndSelect: $root.isTaskSelected($data)">
                        <input data-bind="value: name, event: { blur: $root.clearTask }" />
                    </span>  
                </div>
                <div class="accordion-content ui-widget-content">
                    <span data-bind="visible: !$root.isDescriptionSelected($data)">
                        <a href="#" data-bind="text: description, click: $root.selectedDescription"></a>
                    </span>
                    <span data-bind="visibleAndSelect: $root.isDescriptionSelected($data)">
                        <input data-bind="value: description, event: { blur: $root.clearDescription }" />
                    </span>
                </div>
            </div>
        </div>   
    </script>
</div>

<div id="results">
    <h3>High Priority</h3>
    <ul...

CSS

body {
    font-family: arial;
}

h3 {
    font-weight: bold;
    text-align: center;
}

div {
    padding: 5px;
    margin: 5px;
    border: black 1px solid;
}

p, a {
    font-size: .8em;
}

ul {
    padding-bottom: 10px;
}

.ko_container {
    width: 250px;
    min-height: 50px;
    background-color: #AAA;
}

.high {
    background-color: red;
}

.trash {
    background-color: #000;
}

.item {
    background-color: #DDD;
    cursor: move;
    text-align: center;
}

.item input {
    width: 200px;
}

#main {
    float: left;
    width: 275px;
    margin-top: 0px;
}

#results {
    margin-left: 300px;
    width: 275px;
}
#debug {
    margin-left: 300px;
     width: 275px;
    font-size:11px;
    border: none;
}

JavaScript

ko.bindingHandlers.accordion = {
    init: function(element, valueAccessor) {
        var options = valueAccessor() || {};
        setTimeout(function() {
            $(element).accordion(options);
        }, 0);
        
        //handle disposal (if KO removes by the template binding)
          ko.utils.domNodeDisposal.addDisposeCallback(element, function(){
              $(element).accordion("destroy");
          });
    },
    update: function(element, valueAccessor) {
        var options = valueAccessor() || {};
        $(element).accordion("destroy").accordion(options);
    }
};


//control visibility, give element focus, and select the contents (in order)
ko.bindingHandlers.visibleAndSelect = {
    update:function (element, valueAccessor) {
        ko.bindingHandlers.visible.update(element, valueAccessor);
        if (valueAccessor()) {
            setTimeout(function () {
                $(element).find("input").focus().select();
            }, 0); //new tasks are not in DOM yet
        }
    }
};

var Task = function (data) {
    this.taskID = ko.observable(data.taskID);
    this.name = ko.observable(data.name);
    this.description = ko.observable(data.description);
};

var ViewModel = function () {
    var self = this;

    self.selectedItem=ko.observable();
    self.highPriorityTasks = ko.observableArray([
        new Task({taskID:1, name: "Get dog food", description: "Buy dog food, open can, serve"}),
        new Task({taskID:2, name: "Mow lawn", description: "Find mower, fill petrol, start!"}),
        new Task({taskID:3, name: "Fix car", description: "Call workshop, drive there"})
    ]);
    self.highPriorityTasks.id = "high";

    self.normalPriorityTasks = ko.observableArray([
        new Task({taskID:4, name: "Fix fence", description: "Get hammer & nails"}),
        new Task({taskID:5, name: "Walk dog", description: "Track down dog"}),
        new Task({taskID:6, name: "Read book", description: "Find book, avoid falling asleep"})
    ]);
   ...