Selection Managment in Windows Store App

Introduction

In this article I describe how to create Windows Store Apps for managing Item Selection using JavaScript. This app shows how to programmatically manipulate the selection of the ListView. Use the buttons to select all items, or clear the current selection. To retrieve and display which items are selected, press the Report Selection button.

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 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.

Write the following code in the default.html

<!DOCTYPE html>

<html>

<head>

</head>

</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).then(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>

<head>

</head>

<body>

<button id="selectAll">Select all </button>

<button id="clearSelection">Clear all</button>

<button id="reportSelection">Report</button>

</div>

</div> </div> </div>

<div id="listView"

class="win-selectionstylefilled"

data-win-control="WinJS.UI.ListView"

data-win-options="{ itemDataSource: myData.dataSource,

itemTemplate: smallListIconTextTemplate,

selectionMode: 'multi',

tapBehavior: 'toggleSelect',

layout: { type: WinJS.UI.GridLayout }

></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) {

var listView = element.querySelector('#listView').winControl;

listView.forceLayout();

function reportSelection() {

var selectionCount = listView.selection.count();

if (selectionCount > 0) {

listView.selection.getItems().done(function (currentSelection) {

var itemsSelectedString = selectionCount + " ";

if (selectionCount === 1) {

itemsSelectedString += "item is currently selected. Specifically, item ";

} else {

itemsSelectedString += "items are currently selected. Specifically, items ";

}

var numItemsReported = 0;

currentSelection.forEach(function (selectedItem) {

numItemsReported++;

if (numItemsReported !== selectionCount) {

itemsSelectedString += selectedItem.index + ", ";

} else {

itemsSelectedString += selectedItem.index;

if (selectionCount === 1) {

itemsSelectedString += " is selected.";

} else {

itemsSelectedString += " are selected.";

} } });

WinJS.log && WinJS.log(itemsSelectedString, "app", "status");

});

} else {

WinJS.log && WinJS.log("No items are currently selected.", "app", "status");

} }

function selectAll() {

WinJS.log && WinJS.log(" ", "app", "status");

listView.selection.selectAll();

}

function clearSelection() {

WinJS.log && WinJS.log(" ", "app", "status");

listView.selection.clear();

}

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

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

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

} });

})();

var myData = new WinJS.Binding.List([

{ title: "D", text: "", picture: "/images/1.jpg" },

{ title: "D", text: "", picture: "/images/2.jpg" },

{ title: "D", text: "", picture: "/images/3.jpg" },

{ title: "D", text: "", picture: "/images/4.jpg" },

]);

Output

Summary

In this article I described how to create a Windows Store App for managing Item Selection 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.