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POiPhone - dequeueReusableCellWithIdentifier usage
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copied!<p>I'm working on a iPhone app which has a pretty large UITableView with data taken from the web, so I'm trying to optimize its creation and usage.</p> <p>I found out that <code>dequeueReusableCellWithIdentifier</code> is pretty useful, but after seeing many source codes using this, I'm wondering if the usage I make of this function is the good one.</p> <p>Here is what people usually do:</p> <pre><code>UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:@"Cell"]; if (cell == nil) { cell = [[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:@"Cell"]; // Add elements to the cell return cell; </code></pre> <p>And here is the way I did it:</p> <pre><code>// The cell row NSString identifier = [NSString stringWithFormat:@"Cell %d", indexPath.row]; UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:identifier]; if (cell != nil) return cell; cell = [[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:identifier]; // Add elements to the cell return cell; </code></pre> <p>The difference is that people use the same identifier for every cell, so dequeuing one only avoids to alloc a new one.</p> <p>For me, the point of queuing was to give each cell a unique identifier, so when the app asks for a cell it already displayed, neither allocation nor element adding have to be done.</p> <p><i>In fine</i> I don't know which is best, the "common" method ceils the table's memory usage to the exact number of cells it display, whilst the method I use seems to favour speed as it keeps all calculated cells, but can cause large memory consumption (unless there's an inner limit to the queue).</p> <p>Am I wrong to use it this way? Or is it just up to the developer, depending on his needs?</p>

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