Adding a search barr to RSS reader

[jcww33]

Hello,
I followed the tutorial available at Iphone Tutorial: Creating a RSS Feed Reader and wanted to add a search bar to the tableview and have it search the contents of the table. I Googled it and found nothing that worked. Any help that you could offer would be greatly appreciated.


Thanks!

[DenVog]

Originally Posted by jcww33

Hello,
I followed the tutorial available at Iphone Tutorial: Creating a RSS Feed Reader and wanted to add a search bar to the tableview and have it search the contents of the table. I Googled it and found nothing that worked. Any help that you could offer would be greatly appreciated.


Thanks!

Have you had a look at Brian Slick's UITableView How-To: Part 2 - Search

[jcww33]

Originally Posted by DenVog

Have you had a look at Brian Slick's UITableView How-To: Part 2 - Search

Yes, the app crashes when I type a character in a search bar.

[BrianSlick]

Ah, you must be the anonymous person who had the same problem as someone else, provided no more information, yet for some reason expected a different answer.

So, repeating that answer: my money is on a memory management issue in your parser.

Edit: at quick glance, that parser is leaking horribly. Leaks don't crash, but when I see memory management done that badly, I'm not at all surprised that something would be over-released or under-retained.

[jcww33]

Originally Posted by BrianSlick

Ah, you must be the anonymous person who had the same problem as someone else, provided no more information, yet for some reason expected a different answer.

So, repeating that answer: my money is on a memory management issue in your parser.

Edit: at quick glance, that parser is leaking horribly. Leaks don't crash, but when I see memory management done that badly, I'm not at all surprised that something would be over-released or under-retained.

Yep, you guessed it. I guess I was hoping you would elaborate. I ran Instruments and found a ton of leaks. Tried releasing everything allocated and there is still a ton of errors. Care to help. Thank you so much for your helpful tutorial.

[BrianSlick]

The parser needs to be using properties correctly. Fixing that will go a long way.

[jcww33]

Originally Posted by BrianSlick

The parser needs to be using properties correctly. Fixing that will go a long way.

Really? @synthesize is used in the .m

[BrianSlick]

Read the properties link in my signature.

[jcww33]

Hm, very interesting. So your saying I should be using self?

[BrianSlick]

Was that not stated clearly enough in the other thread?

[jcww33]

Yes, however i'm confused how this is done incorrectly. Maybe i'm not understanding something yet you state in the post is that you create an object, do something with it, and release it. The parser releases everything in the dealloc so I added self to each release and that didn't help. Thank you so much for helping me!

[BrianSlick]

Don't make me guess what you are doing. Post some code.

[jcww33]

Ok, so I added self so it looks like this:

[[self items] release];
[[self responseData] release];
[[self currentTitle] release];
[[self currentDate] release];
[[self currentSummary] release];
[[self currentLink] release];
[[self currentPodcastLink] release];

and made sure item and current element had an @property and synthesized

[BrianSlick]

Never do that. That's just making things worse. What in the other thread lead you to believe that is what you should do?

Keep rereading the properties thread until this stuff sinks in. You have to understand it.

[jcww33]

Oops, i'll read it a couple times over. I think I need to add self to the methods in the Parser.

[jcww33]

Originally Posted by jcww33

Oops, i'll read it a couple times over. I think I need to add self to the methods in the Parser.

Ok, so I think a major issue is in the parser didStartElement void statement. In your common mistakes post, you talk about how you shouldn't combine alloc/init and self in the same line. This is what's done in the parser didStartElement void. You also state that the parser should autorelease the objects. However, the objects are used later in the code. So when should I release this objects? Or am I reading this all wrong?

[BrianSlick]

Those are problems, yes. Certainly not the only ones.

Autorelease doesn't mean the object dies. It means release later. This balances the alloc.

Keep rereading the properties thread. I think you're starting to head towards understanding, but you're not quite there yet.

[jcww33]

Originally Posted by BrianSlick

Those are problems, yes. Certainly not the only ones.

Autorelease doesn't mean the object dies. It means release later. This balances the alloc.

Keep rereading the properties thread. I think you're starting to head towards understanding, but you're not quite there yet.

Focusing on the parser didStartElement, the whole thing is coded in dot syntax. This is confusing me. How do I convert it so it is no longer written in dot syntax so I can autorelease it?

[BrianSlick]

The syntax doesn't matter. And the difference is mentioned in the properties thread.

As it stands now:

self.currentTitle = [[NSMutableString alloc] init];

As it should be:

self.currentTitle = [[[NSMutableString alloc] init] autorelease];

Or: (I don't like dot syntax)

[self setCurrentTitle:[[[NSMutableString alloc] init] autorelease]];

[jcww33]

So I made the corrections. Still dosen't work. I am confused as to what else is leaking.

[BrianSlick]

Originally Posted by BrianSlick

Don't make me guess what you are doing. Post some code.

.

[jcww33]

Originally Posted by BrianSlick

.

if ([elementName isEqualToString:@"item"]) {
self.item = [[[NSMutableDictionary alloc] init] autorelease];
self.currentTitle = [[[NSMutableString alloc] init] autorelease];
self.currentDate = [[[NSMutableString alloc] init] autorelease];
self.currentSummary = [[[NSMutableString alloc] init] autorelease];
self.currentLink = [[[NSMutableString alloc] init] autorelease];
self.currentPodcastLink = [[[NSMutableString alloc] init] autorelease];
}

[BrianSlick]

Those weren't the only problems in the code.

[jcww33]

Originally Posted by BrianSlick

Those weren't the only problems in the code.

Yes, I know however can't find many others. I did the same thing under the connection didFailWithError

 UIAlertView * errorAlert = [[[UIAlertView alloc] initWithTitle:@"Error loading content" message:errorString delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil] autorelease];

However other then that, anywhere else something is allocated, I try autoreleasing it and get no errors/warnings yet the app crashes.

[BrianSlick]

Leaks don't cause crashes. Crashes (assuming a memory-related issue) will be due to (at least) one of the following:

1. Something is over-released

2. Something is under-retained

I already stated this before.

Don't just go around blindly slapping autoreleases on things. You potentially cause more problems, or make existing problems worse.

Also, it's possible that you have fixed the parser, and now have problems in the rest of your app.