Angular Starter

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Angular Starter

Two simple angular projects.

Be sure that Python is on your path. It should be in C:\Python34.

Step One

Create folder called Week03-AngularStarter-Add. Inside it, save the following as index.html:

<!DOCTYPE HTML>
<html>
    <head>
        <meta charset="utf-8">        
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <title>Angular Starter Add</title>
        <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.5.3/angular.min.js"></script>
    </head>
    <body data-ng-app>
        <h1>Angular Starter Add</h1>

        <p>5 * 7 = {{5 * 7}}</p>

    </body>
</html>

The file shown here looks like HTML at first, but there a odd bits of syntax. Notice, for instance, these two bits of syntax:

These two bits of syntax indicate that this is not raw HTML. Instead, it is an angular template.

Nomenclature:

We often write data-ng-app in order to conform with the rules of HTML5. Both ng-app and data-ng-app have the same meaning and work in most browsers. A syntax checker will choke on ng-app, but will approve data-ng-app

Step Two

We now want to view our work in a browser. I would prefer that you launch this file, and all files we create, from a web server rather than from the file system. For details on the difference, see this section on Elvenware.

On Cloud Nine open your file in the editor and press the green Run button. A window will open with contents similar to the following:

Starting Apache httpd, serving https://prog219-calvert-2016-ccalvert.c9users.io/Foo/foo.html. Started apache2

Left click on the URL and choose and open or open in preview.

If you are running on Pristine Lubuntu, Windows or some other OS, then take a slightly different approach. In the same directory as you HTML file, create a batch file called StartPythonWebServer.bat or a shell script called StartPythonWebServer. Place the following in your inside it:

python3 -m http.server 30025

Run the batch file and browse to http://localhost:30025.

Step Three

Make the application interactive by allowing user input.

Here is how to create an input control:


Here is how to use the ng-model declared in the input control:

5 * 7 = {{operandA * 7}}

The model declared in the input control now appears automatically in the

Fiddle with it until entering 2 and 5 in the input controls yields this output:

2 * 5 = 10

Reference:

Step Four

Create a folder called Week02-AngularStarter-Lists

If necessary, inside the folder put your StartPythonWebServer file. Also add the following as index.html:

<!DOCTYPE HTML>
<html>
    <head>
        <meta charset="utf-8">        
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <title>Angular Starter Lists</title>
        <script src="bower_components/angular/angular.js"></script>
    </head>
    <body ng-app="main">
        <h1>Angular Starter Lists</h1>

        <p>Enter a name and I will add it to our list.</p>
        <input type="text" ng-model="listItem"  placeholder="Enter list item name">

        <p>You entered: {{listItem}}</p>

    </body>
</html>

Step Five

Type bower init to create a bower.json file. Fill in the fields according to your common sense. You can accept the defaults for all questions, or fill in a few with useful values. There is no need to create a .bowerrc file.

Add angular to your bower file:

bower install angular --save

Step Six

Create a file called index.js in the root of your AngularStarter-Lists project. Place the following code in it:

(function() {

    var app = angular.module('main', []);

    app.controller('ListControl', function($scope) {

        'use strict';        

        var listData = [
            { text : 'Attend class at BC', done : false },
            { text : 'Complete JavaScript programs', done : false }
        ];

        $scope.todoList = listData;   
    });
})();

Be sure to load index.js in your HTML template:

<head>
    <meta charset="utf-8">        
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Angular Starter Lists</title>
    <script src="bower_components/angular/angular.js"></script>
    <script src="index.js"></script>
</head>

Take all of the code in the body of index.html and wrap it in a DIV:

// PUT THE CODE FROM THE BODY HERE

You will end up with an H1 tag, two P tags, and an INPUT tag inside your DIV. Note that the DIV is an Angular Controller. Though this program uses $Scope most of the time, note that this Controller at least supports ControllerAs syntax.

And in the angular HTML template, just below the {{listItem}} expression:

    
  • {{todo.text}}

Step Seven

Add the following code to your index.js file just beneath the todo list:

    $scope.listItem = "New Item";
    $scope.itemCount = getItemCount();

Since the above code uses $scope it has to be inside your Controller.

Still working inside the controller, add the following methods:

       $scope.addTodo = function() {
            $scope.todoList.push({
                text : $scope.listItem,
                done : false
            });
            $scope.listItem = '';
            $scope.itemCount = getItemCount();
        };

        function getItemCount() {            
            var count = 0;
            angular.forEach($scope.todoList, function(todo) {
                count += todo.done ? 0 : 1;
            });
            return count;
        };

Now switch to the HTML and add a FORM with an INPUT control and a BUTTON. It goes under the text that asks for user input:

Items in list: {{itemCount}}

When done, the Controller in my HTML has the following HTML tags, shown in the order in which they appear:

The result looks like this:

Angular Starter List

Turn it in

Push both your folders to your git repository. When you submit the assignment, provide the URL of your repository. If you have not used the exact names for the folders that I specify here, also submit your folder names.

Hints

Do not submit nested folders of this type:

/Git/Week03-MyProject/MyProject

In the bad scenario, the /Git/Week02-MyProject folder is empty except for the sub-directory. Don't do that. Instead, copy of the contents of MyProject into Week02-MyProject and then delete the empty MyProject folder.

NOTE: In the "bad scenario" outlined above, the exact name of your folders may differ. The point is not to submit your project inside a nested set of folders. It is, of course, legitimate to have folders with names like views or routes. They are just parts of the project.

Errors

Suppose you get an error like this:

angular.js:68 Uncaught Error: [$injector:modulerr]
Failed to instantiate module main due to:
Error: [$injector:nomod] Module 'main' is not available!
You either misspelled the module name or forgot to load it.
If registering a module ensure that you specify the dependencies as the second argument.
var app = angular.module('main', []);