ListDataSource in Windows Store App

In this article I describe how to create Windows Store Apps for ListDataSource using JavaScript.

Introduction

In this article I describe how to create Windows Store Apps for ListDataSource using JavaScript. This app demonstrates how to use the ListDataSource API to programmatically manipulate items in a ListView. This can be used with all datasources, unlike Binding.List which is unique to it.

I assume you can create a simple Windows Store App using JavaScript; for more help visit Simple Windows Store Apps using JavaScript. In my previous article I discribe Binding.List; see: Binding.List Windows Store App.

To start the creation of the apps, add one JavaScript page by right-clicking on the js folder in the Solution Explorer and select "Add" > "New item" > "JavaScript Page" and then provide an appropriate name. In the same way, add a HTML page to your project.

listdatasource_in-windows-store--app.jpg

Write the following code in the default.html:

<!DOCTYPE html>

<html>

<head>    

    <title></title>

    <link rel="stylesheet" href="//Microsoft.WinJS.1.0/css/ui-light.css" />

    <script src="//Microsoft.WinJS.1.0/js/base.js"></script>

    <script src="//Microsoft.WinJS.1.0/js/ui.js"></script>

    <link rel="stylesheet" href="/css/default.css" />

    <script src="/js/default.js"></script>

</head>

<body role="application"style="background-color:lightpink">

    <center><div id="rootGrid">

        <div id="content">

            <h1 id="featureLabel"></h1>

            <div id="contentHost"></div>

        </div>

    </div></center>

</body>

</html>

Write the following code in the default.js:

(function () {

    "use strict";

    var appTitle = "";

    var pages = [

        { url: "page.html"}

    ];

    function activated(eventObject) {

        if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) {

            eventObject.setPromise(WinJS.UI.processAll().then(function () {

                var url = WinJS.Application.sessionState.lastUrl || pages[0].url;

                return WinJS.Navigation.navigate(url);

            }));

        }

    }

    WinJS.Navigation.addEventListener("navigated", function (eventObject) {

        var url = eventObject.detail.location;

        var host = document.getElementById("contentHost");

        host.winControl && host.winControl.unload && host.winControl.unload();

        WinJS.Utilities.empty(host);

        eventObject.detail.setPromise(WinJS.UI.Pages.render(url, host, eventObject.detail.state).done(function () {

            WinJS.Application.sessionState.lastUrl = url;

        }));

    });

    WinJS.Namespace.define("App", {

        appTitle: appTitle,

        pages: pages

    });

    WinJS.Application.addEventListener("activated", activated, false);

    WinJS.Application.start();

})(); 


Write the following code in the page.html:

<!DOCTYPE html>

<html>

<head>

    <title></title>

    <script src="/js/script.js"></script>

</head>

<body>

    <div data-win-control="App.pageInput">

   

        <div>

            <button id="shuffle" class="action secondary">

                Shuffle Nomber

            </button>        

            <button id="addnomber" class="action secondary">

                Add a random Nomber

            </button>

        </div>

    </div>

    <div data-win-control="App.pageOutput">

        <div id="nomberTemplate" data-win-control="WinJS.Binding.Template">

            <div class="nomberTempl">

                <h6 class="counter" data-win-bind="innerText: counter"></h6>

                <h1 class="letter" data-win-bind="innerText: letter"></h1>

            </div>

        </div>

        <div id="listView3" class="box win-selectionstylefilled" data-win-control="WinJS.UI.ListView" data-win-options="{ selectionMode: 'multi', reorderable: true, layout: { type: WinJS.UI.GridLayout, maxRows: 1 } }">

        </div>

    </div>

</body>

</html>

Write the following code in the script.js:
 

(function () {

    "use strict";

    var page = WinJS.UI.Pages.define("page.html", {

        ready: function (element, options) {

            element.querySelector("#shuffle").addEventListener("click", shufflenombers, false);

            element.querySelector("#addnomber").addEventListener("click", addnomber, false);

            initnombers();

        }

    });

    var _tIndex = 0;

    var _letterSrc = "1234567890".split("");

    function initnombers() {

        var letters = [];

        for (var i = 0; i < 7; i++) {

            letters[i] = generatenomber();

        }

        var lettersList = new WinJS.Binding.List(letters);

        var list2 = document.getElementById("listView3").winControl; 

        list2.itemDataSource = lettersList.dataSource;

        list2.itemTemplate = document.getElementById("nomberTemplate");

        list2.forceLayout();

    }

    function generatenomber() {

        var nomber = {

            letter: _letterSrc[Math.floor(Math.random() * _letterSrc.length)],

            counter: _tIndex

        };

        _tIndex++; 

        return nomber;

    }

    function shufflenombers() {

        var ds = document.getElementById("listView3").winControl.itemDataSource;

        ds.getCount().done(function (count) {

            if (count > 0) {

                var binding = ds.createListBinding();

                var keys = [], p = [];

                for (var i = 0; i < count; i++) {

                    (function (j) {

                        p[j] = binding.fromIndex(j).then(function (currentItem) {

                            keys[j] = currentItem.key;

                        });

                    })(i);

                }

                WinJS.Promise.join(p).done(function () {

                    binding.release();

                    ds.beginEdits();

                    for (var itemIndex = 0; itemIndex < count; itemIndex++) {

                        var randomIndex = Math.floor(Math.random() * (count - itemIndex));

                        if (randomIndex < 0 || randomIndex === keys.length) { debugger; }

                        var key = keys[randomIndex];

                        keys.splice(randomIndex, 1);

                        ds.moveToStart(key);

                    }

                    ds.endEdits();

                });

            }

        });

    }

    function addnomber() {

        var ds = document.getElementById("listView3").winControl.itemDataSource;

        ds.beginEdits();

        var nomber = generatenomber();

        ds.insertAtEnd(null, nomber);

        ds.endEdits();

    } 

})();

Output:

listdatasource_in-windows-store--apps.jpg

Summary

In this article I described how to create a Windows Store App for ListDataSource using JavaScript. I hope this article has helped you to understand this topic. Please share it. If you know more about this, your feedback and constructive contributions are welcome.