Join Bill Weinman for an in-depth discussion in this video Deleting feeds, part of iOS SDK and SQLite: Building Data-Driven Apps (2013).
Now that we can add feeds, we should be able to delete feeds, too.…Cocoa Touch has a neat UI for this.…You can press an Edit button which will reveal special red delete icons, or you can swipe to delete.…This interface is easy to implement, and because it's so common, it will be familiar to the user.…So, we'll start by making a working copy of BWRSS-addView-05, and we'll rename it as 06.…So, I'm going to use the done version here. And you can use the done version or you can…use the version that you created in the last movie if you've been following along.…
And I'm going to open this in Xcode by double-clicking on the Xcode project file. And we're going…to come back out here to the Finder and I'm going to open this 06-methods.txt file.…And it just has this one method in it, and I'm going to copy that and come over in to Xcode and we'll paste it in.…We're going to put this right at the end of the tableView section.…We'll go ahead and delete all of this, and we'll just paste it in right there.…
- Prototyping the app
- Coding and working with a testbed
- Creating an Objective-C interface for SQLite
- Designing a database schema
- Creating the view controllers
- Reading and writing to the database
- Parsing the RSS feed with NSXMLParser
- Updating the item view with feed items
- Implementing the pull to refresh gesture for iOS 6
- Creating a universal application with multiple views
Skill Level Intermediate
Q: Why is the RSSDB library in the exercise files different than the one in the videos?
<p>A: The RSSDB library had to be updated to work around a bug in the iOS 7 SDK.</p> <p>There is a bug in the iOS 7 SDK that prevents the BWDB fast enumeration implementation from working on a device. The symptom is code that runs fine on the emulator, but not on a device. iOS devices use an ARM processor, while the emulator runs on your Mac's Intel processor. This points to the LLVM ARM code generator as the source of the bug. Because the bug appears to be in the LLVM compiler, it may be some time before it is fixed.</p> <p>As a workaround we have changed the getFeedIDs and getItemIDs methods in the RSSDB library so they don't use Objective C fast enumeration. </p> <p>Please note that this same bug also affects some of the BWDB testbed code in Chapter 2. The result is that it will run on the emulator but not on a device.</p>
Q: After upgrading to Xcode 5.1 I get an error that says: <blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;"> <p>"Used type va_list (aka_builtin_va_list) where arithmetic or pointer type is required"</p> </blockquote>
A: Please download the exercise files again to get the latest version of the BWDB library.
Q: I'm using Xcode 6. Why am I getting error messages with the exercise files?
<div>A: A lot has changed in iOS since this course was released. The author is in the process of rewriting the code and updating the course for iOS 8. In the meantime he has prepared a version of the app that works in iOS 8 and Xcode 6. Download it here: </div> <div> </div> <div>http://ios.bw.org/ </div> <div> </div>