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is possible. However, there are some common problematic points in JavaScript
development.
For example, there is the compatibility problem among different Web browsers.
The standardization process of HTML5 is not completed yet. In addition, Web
browser vendors compete each other for getting more shares by implementing
attractive new functionalities. As a result, depending on browsers, some func-
tionalities are implemented in some browser, but others are not. HTML5 spec-
ification is changing this situation, but some differences among browsers still
remain.
Moreover, the language specification of JavaScript itself has some diculties
for large-scale software development. JavaScript is a flexible, powerful program-
ming language and easy to learn. People can quickly write a few JavaScript
codes to set up simple interactivity on their Web sites. Nevertheless, because it
is a weakly typed and interpreted language, its development process is dicult
to be supported by Integrated Development Environments (IDEs). Nowadays,
some powerful IDEs are produced for JavaScript development. However, it is
still not so matured as on other strongly typed, compiled languages like Java or
C++. Furthermore, there is different syntaxtodothesamethingsbecauseof
its flexibility.
3.2 An MVC Framework: AngularJS
To solve those problems, some software companies and JavaScript developers
produce JavaScript libraries or frameworks. jQuery
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is one of the most popu-
lar and powerful JavaScript libraries. It provides a uniform way and syntax to
manipulate DOM structure and CSS properties. It is often used for building
interactive user interface on Web sites. A lot of developers provide plugins of
jQuery; therefor extensively its functionalities are expanded. However, it does
not provide a uniform way to structure software like MVC, leaving it entirely to
developers.
Nowadays, there exist many JavaScript MVC (or MV*) frameworks [10] such
as Backbone
5
, Ember.js
6
, and Knockout
7
. We selected AngularJS as the basic
framework of the meme media platform out of those many frameworks. Angu-
larJS is developed by Google and has a large developer community. It supports
composite views, data-binding between model and view, and custom vocabulary
definition by detectives.
Figure 3 shows an overview of AngularJS's architecture and its composition
structure of composite views. It looks totally different from the original MVC
structure
8
, but it has clear separation of roles of components. Here, models can be
any JavaScript objects. Views are DOM fragments rendered in a browser window.
8
Some people call it MVW (Model-View-Whatever) framework.
