This is the forth iphone programming tutorial in the iPhone Rss Reader app example. In this iphone source code example, I will improve the xml parser to get more data from rss feed xml, and store them in a new value object class. When user clicks the rss title in the table view, I will use push segue to switch to a UIWebView, which will show the rss content inside.

This tutorial will update the storyboard to add a new UIViewController, and all data in this UIWebView example is generated by the previous iphone example source code. Hence, I recommend you to review the whole example tutorials as well.

• iPhone Rss Reader App IOS Tutorial 1: StoryBoard UI Programming
• iPhone Rss Reader App IOS Tutorial 2: HTTP Network Programming in IOS
• iPhone Rss Reader App IOS Tutorial 3: XML Parser in IOS
• iPhone Rss Reader App IOS Tutorial 4: Show Rss Feed HTML in UIWebView

In tutorial 3, I already show you the rss feed content example. It is an xml file which groups the rss content by <item> <title> <link> and <content>. You can check this link to see the rss feed data:

http://jmsliu.com/feed

To store the rss feed content, I’ve created a new value object class named RssData. It is a pure value class which only contains variables inside. Here is the example source code:
[java]
#import “RssData.h”

@implementation RssData
@synthesize title;
@synthesize link;
@synthesize content;
@synthesize publishDate;
@end
[/java]

In the xml, content tag is a little bit different from any other tags. All content data is around by <![CDATA[ and ]]>. Hence, I will choose another function, foundCDATA(), to get the content data in RssXMLParser.m. Additionally, I also make a change to store the data from rss feed. In previous example, I was using NSMutableDictionary to store the title and link of the rss item. This time, I will use my new value object class. Therefore, I am using NSMutableArray instead. Let’s see the code example:
[java]
- (void) parseRssXML:(NSData *)xmldata
{
articles = [[NSMutableArray alloc] init];
NSXMLParser *xmlParser = [[NSXMLParser alloc] initWithData:xmldata];
[xmlParser setDelegate:self];
[xmlParser setShouldResolveExternalEntities:NO];
[xmlParser parse];
}

-(void) parser:(NSXMLParser *)parser foundCDATA:(NSData *)CDATABlock
{
if (aNode == content)
{
RssData *rss = [articles lastObject];
rss.content = [[NSString alloc] initWithData:CDATABlock encoding:NSUTF8StringEncoding];
}
}
[/java]
Please pay attention on the change of articles variable, it is defined as NSMutableArray. The usage is quite different from IOS Tutorial 3.

We are getting the data ready. Next step, I will drag a new UIViewController into storyboard and put a UIWebView in the new UIViewController. This will be the view controller to show the rss feed html content. Then, I create a new class RssViewController, which will linked to the new UIViewController. Here is the example code for RssViewController.m:
[java]
@implementation RssViewController
@synthesize rssWebView;
@synthesize rssData;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}

- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn’t have a superview.
[super didReceiveMemoryWarning];

// Release any cached data, images, etc that aren’t in use.
}

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
NSString *htmlContent = rssData.content;
htmlContent = [NSString stringWithFormat:@"%@

%@

%@%@", HTML_HEADER, rssData.title, rssData.publishDate, htmlContent, HTML_FOOTER];
[rssWebView loadHTMLString:htmlContent baseURL:nil];
}

- (void)viewDidUnload
{
[self setRssWebView:nil];
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return YES;
}
[/java]

Now, we have to link the RssTableViewController and RssViewController with a push segue. To make the push segue working, we have to embed the RssTableViewController with UINavigation Controller. The following video will show you how to embed UIViewController with UINavigationController in the storyboard and how to create a push segue between UITableViewController and normal UIViewController.

The last step, we have to add another piece of code in RssTableViewController, so that rss reader can show the rss content in the UIWebView after we click the item in table view. Here is the code example:
[java]
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if([[segue identifier] isEqualToString:@”showRssSegue”])
{
int index = [self.tableView indexPathForSelectedRow].row;
RssData *data = [articlesList objectAtIndex:index];
RssViewController *rc = [segue destinationViewController];
[rc setRssData:data];
[rc.navigationItem setTitle:data.title];
}
}
[/java]

That’s all. Now we have finished a real iPhone app which can load and read the rss feed from a website. If you want to make some money with this app, I suggest you to add AdMob advertisement bar in the header or footer of the app. You can find this tutorial at Add Google Admob in IOS Apps

Get Full Source Code under $5.99

You will get whole iPhond Rss Reader App source code at $5.99. It is fully functional, and embedded the Google AdMob module by default. With this source code, you can do everything you want:

• Load your website rss feed;
• Monetize the app with your own AdMob publish id;
• Use the source code in your own project;
• Publish this app with your apple developer account;