Iphone xcode simulator crashes when I move up and down on a table row - iphone

Question

I can't get my head round this. When the page loads, everything works fine - I can drill up and down, however 'stream' (in the position I have highlighted below) becomes not equal to anything when I pull up and down on the tableview. But the error is only sometimes. Normally it returns key/pairs.
If know one can understand above how to you test for // (int)[$VAR count]} key/value pairs
in a NSMutableDictionary object
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *FirstLevelCell = #"FirstLevelCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:FirstLevelCell];
if(cell == nil)
{
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:FirstLevelCell] autorelease];
}
NSInteger row = [indexPath row];
//NSDictionary *stream = (NSDictionary *) [dataList objectAtIndex:row];
NSString *level = self.atLevel;
if([level isEqualToString:#"level2"])
{
NSMutableDictionary *stream = [[NSMutableArray alloc] init];
stream = (NSMutableDictionary *) [dataList objectAtIndex:row];
// stream value is (int)[$VAR count]} key/value pairs
if ([stream valueForKey:#"title"] )
{
cell.textLabel.text = [stream valueForKey:#"title"];
cell.textLabel.numberOfLines = 2;
cell.textLabel.font =[UIFont systemFontOfSize:10];
NSString *detailText = [stream valueForKey:#"created"];
cell.detailTextLabel.numberOfLines = 2;
cell.detailTextLabel.font= [UIFont systemFontOfSize:9];
cell.detailTextLabel.text = detailText;
NSString *str = #"http://www.mywebsite.co.uk/images/stories/Cimex.jpg";
NSData *imageURL = [[NSData alloc] initWithContentsOfURL:[NSURL URLWithString:str]];
UIImage *newsImage = [[UIImage alloc] initWithData:imageURL];
cell.imageView.image = newsImage;
[stream release];
}
}
else
{
cell.textLabel.text = [dataList objectAtIndex:row];
}
return cell;
}
Thanks for your time

Answer 1

You are both leaking and over-releasing the stream dictionary:
NSMutableDictionary *stream = [[NSMutableArray alloc] init]; // <-- Create a new dictionary
stream = (NSMutableDictionary *) [dataList objectAtIndex:row]; // <-- Overwrite the reference with another dictionary. Previous dictionary is lost...
...
[stream release]; // <-- You are releasing an object you don't have the ownership.
You should remove the dictionary creation as it is useless and the release as you don't own the object.

Answer 2

I didn't really understand the question, but...
You can test for number of values in a dictionary by:
if ([[myDictionary allKeys] count] == someNumber) {
// do something...
}