We will simply print out the value we have seen see listing 4. NSURL is a large class with all sorts of initializers. Email Required, but never shown. This is fairly straightforward, once we have an NSXMLParser object we set the delegate and then call the parse instance method. You may answer your own questions but you are supposed to still follow to form of the site. To track which object we are currently constructing we need an instance variable in the feed object to track the current element. Asked 5 years, 7 months ago. 
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Post as a guest Name. Can you please copy the solution into an answer below so we can upvote it and get this off the unanswered list? This part will look at how to parse the resulting XML data to extract the individual posts.
NSXMLParser
So, when a new element is started, we make sure to nsxmlparxer it out. This simply iterates through our store of posts comparing the unique guid string for each post to determine if we already have this post.
However, when the parsing is complete, how to notify the UI thread that results are available for updating the view? This is fairly straightforward, once we have an NSXMLParser object we set the delegate and then call the parse nsxmlparwer method. Here is a Swift version of the original Objective-C code below.
This is now a formal protocol. To ensure we do not store old objects in the feed we clear out the array holding the posts before we initiate the new network request to retrieve the feed: We also need a temporary instance variable to collect the content of an element as the parser may invoke our delegate multiple times for the same element.
Objective-C Fundamentals - NSXMLParser
The first post covered the retrieval of the feed data over the network. The XML parsing code remains the same. This class implements an event driven parser handling the parsing process by sending messages to a delegate when certain parts of the XML document being parsed are encountered.
Our Post model interface now looks as follows: List of main files of your project The main files are given below screen that is generated when you have created your application. To download the code, login with one of the following social providers. We will simply print out the value we have seen see listing 4. I have also changed the table view controller code to use these modified field names but I will omit that code here.
A typical nxxmlparser, with the most common elements looks something like this:. Running the parser in a separate thread is simple enough.
objective c - NSXMLParser Simple Example - Stack Overflow
The next delegate method that we will implement will be the foundCharacters method which is called each time some content data is encountered: These files are really just XML. If nsxxmlparser want to take a look at the complete Xcode project for the code in this and the previous post you can find it here.
Returns the value set by -setShouldResolveExternalEntities: The reason for this will become clear when we look at the code for parsing the XML. Now directory dialog box will appear.
Called when an event occurs, as their name indicates. We already have a method named feedChanged that is called when the controller receives a notification from our feed object indicating the feed has been successfully reloaded.
When the time spent in each execution of a delegate method is large or the number of executions is many, the main or UI thread may not handle the nxmlparser without unreasonable delays. These are more or less the fields that I want to extract from the feed. Protocols are all over the place when developing for the iPhone.
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NSXMLParser - Foundation | Apple Developer Documentation
Now all that is left to do is create an instance nsxmlparssr our Parser and see it go. Returns the last error produced by parsing if any. Returns the delegate previously set using -setDelegate:
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