Sample Angularjs Application - Kids Alphabets Tutor

User 11707539

4.00/5 (3 votes)

Jul 9, 2015

CPOL

11601

Developed Kids Alphabets Tutor using ng-repeat, ng-bind, ng-hide, setTimeout in AngularJS

Download source code - 271.9 KB

Introduction

This code displays the content in an array collection with a certain time delay. The tip helps newbies in AngularJs. The code demonstrates the usage of ng-repeat, ng-bind, ng-hide. The array is stored in $scope.letters and the setTimeout in the $scope.testname function sets some delay before the div binds the data to itself.

Background

Using AngularJs, we can build the rich client UI. This is one of the mostly used Single page applications in the current web application development.

Using the Code

In the array $scope.letters, we intialized the alphabets to display.

$scope.letters = ['A-Apple', 'B-Ball', 'C-Cat', 'D-Dog', 
'E-Elephant', 'F-Frog', 'G-Girafee', 'H-Horse'];

setTimeout function will set the delay time using the $scope.$apply() in it and finally the value is returned by the $scope.testname to the ng-bind.

<div ng-bind="testname(letter)"> </div>

$scope.testname = function (letter) {
                setTimeout(function () {
                    $scope.test = letter;
                    $scope.$apply();
                }, time);
                time = time + 2000;
                return letter;
            }

Below is the final piece of code to achieve the task.

<html>
<head>
    <title>Angular.js Example</title>
    <script src="Scripts/angular.js"></script>
    <script>
        var nameApp = angular.module('NameApp', []);
        nameApp.controller('NameCtrl', function ($scope) {
            // I initialized only till alphabet 'H'.. Add more if you are topper in LKG.
            $scope.letters = ['A-Apple', 'B-Ball', 'C-Cat', 
            'D-Dog', 'E-Elephant', 'F-Frog', 'G-Girafee', 'H-Horse'];
            var time = 0;
            $scope.testname = function (letter) {
                setTimeout(function () {
                    $scope.test = letter;
                    $scope.$apply();
                }, time);
                time = time + 2000;
                return letter;
            }
        });
    </script>
</head>
<body ng-app="NameApp" ng-controller="NameCtrl">
    <center>
        <h1>Kids Alphabet Tutor</h1><br />
        <div ng-hide="letter" ng-repeat="letter in letters">
            <div ng-bind="testname(letter)"> </div>
        </div>
        <h1>
            {{test}}
            <img src="Images/{{test}}.PNG" 
            width="75px" height="75px" />
        </h1>
    </center>
</body>
</html>

Points of Interest

Image file Name should be the array element names initialized in the $scope.letters.
$scope.$apply() is a must and should be there to work setTimeout.

How It Looks

Reference link: http://dotnetselflearning.blogspot.in/2015/06/using-settimeout-function-in-angularjs.html