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PO
 

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  1. PO
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    <p>The reason for slow scroll of the table view is that you are trying to get the image data for every cell on the main thread. UI is getting blocked while it is going to fetch the image data from the URL and, According to me its not good to download images on main thread while table view is also loaded.</p> <p>Instead of using this approach, You should have to use NSOperationQueue, NSOperation and NSThread for async load of images to the appropriate cell.</p> <p>If you need more help or simple code like 2-3 function to download images async... </p> <p>Here are the functions....</p> <p>Where you are parsing/getting the values only call [self startLoading]; It will load images without blocking UI.</p> <pre><code>- (void) startLoading { NSOperationQueue *queue = [[[NSOperationQueue alloc]init]autorelease]; NSInvocationOperation *op = [[NSInvocationOperation alloc]initWithTarget:self selector:@selector(loadImagesInBackground) object:nil]; [queue addOperation:op]; [op release]; } -(void) loadImagesInBackground { int index = 0; for (NSString urlString in [(Tweet*)[tweetArray objectAtIndex:indexPath.row] image_url]) { NSURL *url = [NSURL URLWithString:urlString]; NSData *data = [[NSData alloc] initWithContentsOfURL:url]; [myImageArray addObject: [UIImage imageWithData:data]]; index++; if(index/3==0) [self.tableView performSelectorOnMainThread:@selector(reloadData) withObject:nil waitUntilDone:YES]; } } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *identifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifier]; if(!cell) { cell = [[[UITableViewCell alloc] initWithStyle:UITableViewStyleGrouped reuseIdentifier:nil] autorelease]; UIImageView *myImage = [[UIImageView alloc]initWithFrame:CGRectMake(6,10,58,60)] ; [myImage setImage: [myImageArray objectAtIndex:indexpath.row]]; [cell.contentView addSubview:myImage]; [myImage release]; } return cell; } </code></pre>
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    1. POiPhone: How to reduce the memory size of the pic
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    1. USRajender Kumar
    1. USRajender Kumar
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    1. CO+1 for background loading. -1 for NSOperationQueue and its friends when ASIHTTPRequest will do so much more with so much less work. Net 0. ;-)
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      1. USDan Ray
 

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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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