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copied!<p>You should use <a href="http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/KeyValueObserving/KeyValueObserving.html" rel="nofollow">KVO (Key-value observing)</a> to detect when there are changes to your dictionary or array - in this case it seems <code>self.testDict</code>.</p> <p>When you receive this notification, use UITableView's <code>-visibleCells</code> method to update only the visible cells - the others will obviously take on their new value when their cell is recycled using <code>-tableView:cellForRowAtIndexPath:</code>.</p> <p>What's required for KVO: Registering/deregistering when views load/change and setting the variable you wish to observe...</p> <pre><code>- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context { if([keyPath isEqual:@"testDict"]) { NSLog(@"KVO change: %@", change); NSArray *visibleCells = [self.myTableView visibleCells]; for(UITableViewCell *cell in visibleCells) { if(/*cell matches the one I'm targeting OR just update regardless*/) // assign value to UILabel } } } // Call this from -viewDidLoad - (void)registerAsObserver { [self addObserver:self forKeyPath:@"testDict" options:NSKeyValueObservingOptionNew context:NULL]; } // Call this from -viewWillDisappear and -viewDidUnload (may not be necessary for -viewDidUnload if already implemented in -viewWillDisappear) - (void)unregisterAsObserver { [self removeObserver:self forKeyPath:@"testDict"]; } </code></pre> <p>Lastly, to update the cell(s) that have changed, call the <code>-reloadRowsAtIndexPaths:withRowAnimation:</code> method to have the underlying system refresh the cell.</p>

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