Create an RSS feed web app for the iPhone/iPod

A week ago I posted an article showcasing a basic RSS feed web app for the iPhone/iPod Touch. In this post I’ll attempt to demonstrate how I built that application so you can make your own. First a little background: Really Simple Syndication (RSS) is a way of keeping up with frequently changing published content. Twitter, for instance, will allow you to subscribe to someone’s tweets using RSS. My web app is designed to allow users to keep up with frequently published Marketplace podcasts on the APM website using a familiar iPod/iPhone interface. Your own web app, however, doesn’t have to be about podcasts, it could work with any RSS feed you want. Here’s how to get started:
[step 1] Download this zip file with the source code.

[step 2] For testing, get yourself setup with Apache & PHP or something like XAMPP (if you don’t know what XAMPP is or how to set it up, click here).

[step 3] Unzip the source code to a folder of your choice (I named mine “rssapp”) located in your htdocs directory of your XAMPP installation.

[step 4] Start your XAMPP Apache server, open a browser and navigate to http://localhost/rssapp or http://localhost/<whatever you named your folder>

[step 5] To make your own application you’ll need to modify some files in the source code you downloaded. Here’s a breakdown of the files/folders in the source code zip file and what their purpose is:

[step 6] The index.php file is used as the main page of the application. The file itself is a modified copy of the index.html file included with the iWebKit demo. It just contains a list of links to other pages that’ll show my RSS feeds (Marketplace, Wait Wait Don’t Tell Me, etc.). The nice thing about this file is that it contains all the code necessary to make a webpage look like an iPhone/iPod app. The file is optional and I simply use it as a list menu to access multiple RSS feeds.

[step 7] The php files in the root directory correspond to each actual RSS feed in my app. There are two versions of each: One displays the podcast links as a list and the other shows more details about each podcast. Below I have highlighted the sections of interest in the Marketplace php list file. Notice that all php files are all pretty similar to each other. Towards the the top of the file I initialize and create a SimplePie object (or feed) with the specific feed URL, then further down I execute methods available on that SimplePie (feed) object to display more information. To see all the methods available, take a look at the /includes/simplepie.inc file.

For those who are a bit more familiar in object oriented programming, I can recommend the NetBeans PHP IDE. It allows you to checkout the latest revision of SimplePie from the SVN repository and it’ll show you a list of the available methods as an autocomplete menu after you create a simplepie object.

Special thanks to:

• Ryan Parman (SimplePie)
• Geoffrey Sneddon (SimplePie)
• Christopher Plieger (iWebKit)

Without their contributions, I would never have been able to build this application.