Reader Level:
Article

Add Songs to Playlist in Windows Store Apps

By Deepak Middha on Oct 10, 2012
In this app I describe how to add a song to the playlist in a Windows Store App using JavaScript.

Introduction

Today we are going to learn how to create a Windows Store App for adding a song to the playlist using JavaScript. This article will add items to the end of an existing playlist (WPL, ZPL, M3U). In the previous article I described how to create and save the media Playlist in Windows Store Apps You can visit it at Media Playlist In Windows Store Apps using JavaScript.

I assume, you can create a simple Windows Store App using JavaScript. For more help visit Simple Windows Store Apps using JavaScript.

To start the creation of the app, add two JavaScript pages by right-clicking on the js folder in the Solution Explorer and select Add > new item > JavaScript Page and then give an appropriate name. In the same way, add one HTML page to your project.

playlist-windows-store-Apps.jpg

Write the following code in default.html:

<!DOCTYPE html>

<html>

<head>

    <meta charset="utf-8" />

    <title>My App</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/script1.js"></script>

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

</head>

<body role="application">

    <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 default.js:
 

(function () {

    "use strict";

    var exTitle = "";

    var Pages = [

        { url: "page.html" }

 

    ];

    var audioExtensions = [".wma", ".mp3", ".mp2", ".aac", ".adt", ".adts", ".m4a"];

    var playlistExtensions = [".m3u", ".wpl", ".zpl"];

    var playlist = null;

    var ensureUnsnapped = function () {

        var success = true;

        if (Windows.UI.ViewManagement.ApplicationView.value === Windows.UI.ViewManagement.ApplicationViewState.snapped) {

            success = Windows.UI.ViewManagement.ApplicationView.tryUnsnap();

        }

        if (!success) {

            WinJS.log && WinJS.log("Unable to unsnap the app.", "ex", "error");

        }

        return success;

    };

 

    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).then(function () {

            WinJS.Application.sessionState.lastUrl = url;

        }));

    });

 

    WinJS.Namespace.define("App", {

        exTitle: exTitle,

        Pages: Pages,

        audioExtensions: audioExtensions,

        playlistExtensions: playlistExtensions,

        playlist: playlist,

        ensureUnsnapped: ensureUnsnapped

    });

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

    WinJS.Application.start();

})();


Write the following code in page.html:
 

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

    <title>Add</title>

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

</head>

<body>

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

        <button id="PickPlaylistButton">Pick playlist</button>

        <button id="PickAudioButton">Pick audio</button>

    </div>

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

    </div>

</body>

</html>


Write the following code in script.js:
 

(function () {

    "use strict";

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

        ready: function (element, options) {

            document.getElementById("PickPlaylistButton").addEventListener("click", loadPlaylist, false);

            document.getElementById("PickAudioButton").addEventListener("click", addSong, false);

        }

    });

 

    function loadPlaylist() {

        if (!App.ensureUnsnapped()) {

            return;

        }

 

        var picker = new Windows.Storage.Pickers.FileOpenPicker();

        picker.suggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.musicLibrary;

        picker.fileTypeFilter.replaceAll(App.playlistExtensions);

 

        picker.pickSingleFileAsync()

            .then(function (file) {

                if (file) {

                    return Windows.Media.Playlists.Playlist.loadAsync(file);

                }

                return WinJS.Promise.wrapError("No file picked");

            }, function (error) {

                WinJS.log && WinJS.log("Error in picking file.", "ex", "error");

            })

            .done(function (playlist) {

                App.playlist = playlist;

                WinJS.log && WinJS.log("Playlist loaded.", "ex", "status");

            }, function (error) {

                WinJS.log && WinJS.log(error, "ex", "error");

            });

    }

    function addSong() {

        if (App.playlist) {

            if (!App.ensureUnsnapped()) {

                return;

            }

            var picker = new Windows.Storage.Pickers.FileOpenPicker();

            picker.suggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.musicLibrary;

            picker.fileTypeFilter.replaceAll(App.audioExtensions);

 

            var numFilesPicked = 0;

            picker.pickMultipleFilesAsync()

                .then(function (files) {

                    if (files.size > 0) {

                        numFilesPicked = files.size;

 

                        files.forEach(function (file) {

                            App.playlist.files.append(file);

                        });

 

                        return App.playlist.saveAsync();

                    }

                    else {

                        return WinJS.Promise.wrapError("No files picked.");

                    }

                })

                .done(function (file) {

                    WinJS.log && WinJS.log(numFilesPicked + " files added to playlist.", "ex", "status");

                }, function (error) {

                    WinJS.log && WinJS.log(error, "ex", "error");

                });

        }

        else {

            WinJS.log && WinJS.log("Pick playlist first.", "ex", "error");

        }

    }

})(); 


Write the following code in script1.js:
 

(function () {

    var PageOutput = WinJS.Class.define(

        function (element, options) {

            element.winControl = this;

            this.element = element;

            new WinJS.Utilities.QueryCollection(element)

                        .setAttribute("role", "region")

                        .setAttribute("aria-labelledby", "outputLabel")

                        .setAttribute("aria-live", "assertive");

            element.id = "output";

 

            this._addOutputLabel(element);

            this._addStatusOutput(element);

        }, {

            _addOutputLabel: function (element) {

                var label = document.createElement("h2");

                label.id = "outputLabel";

                label.textContent = "";

                element.parentNode.insertBefore(label, element);

            },

            _addStatusOutput: function (element) {

                var statusDiv = document.createElement("div");

                statusDiv.id = "statusMessage";

                element.insertBefore(statusDiv, element.childNodes[0]);

            }

        }

    );

    var currentPageUrl = null;

    WinJS.Navigation.addEventListener("navigating", function (evt) {

        currentPageUrl = evt.detail.location;

    });

    WinJS.log = function (message, tag, type) {

        var statusDiv = document.getElementById("statusMessage");

    };

 

    function activated(e) {

        WinJS.Utilities.query("#featureLabel")[0].textContent = App.exTitle;

    }

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

    WinJS.Namespace.define("App", {

        PageOutput: PageOutput

    });

})(); 


Output:


playlist-window-store-app.jpg


media-playlist-windows-store-apps.jpg
Summary

In this app I described how to add a song to the playlist in a Windows Store App 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.

Deepak Middha

Deepak Middha is one time Microsoft MVP(Client App Dev) , working as Sr. Software Developer with lots of hands on experience using ASP.NET 2.0/3.5, AJAX, MVC, C#,  SQL Server 2005/2008/2012, WCF, JQuery and Silverl... Read more

COMMENT USING