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PORetrieve custom prototype cell height from storyboard?
 

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    <p>When using "Dynamic Prototypes" for specifying <code>UITableView</code> content on the storyboard, there is a "Row Height" property that can be set to Custom.</p> <p>When instantiating cells, this custom row height is not taken into account. This makes sense, since which prototype cell I use is decided by my application code at the time when the cell is to be instantiated. To instantiate all cells when calculating layout would introduce a performance penalty, so I understand why that cannot be done.</p> <p>The question then, can I somehow retrieve the height given a cell reuse identifier, e.g. </p> <pre><code>[myTableView heightForCellWithReuseIdentifier:@"MyCellPrototype"]; </code></pre> <p>or something along that line? Or do I have to duplicate the explicit row heights in my application code, with the maintenance burden that follows?</p> <p><strong>Solved, with the help of @TimothyMoose:</strong></p> <p>The heights are stored in the cells themselves, which means the only way of getting the heights is to instantiate the prototypes. One way of doing this is to pre-dequeue the cells outside of the normal cell callback method. Here is my small POC, which works:</p> <pre><code>#import "ViewController.h" @interface ViewController () { NSDictionary* heights; } @end @implementation ViewController - (NSString*) _reusableIdentifierForIndexPath:(NSIndexPath *)indexPath { return [NSString stringWithFormat:@"C%d", indexPath.row]; } - (CGFloat) tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath { if(!heights) { NSMutableDictionary* hts = [NSMutableDictionary dictionary]; for(NSString* reusableIdentifier in [NSArray arrayWithObjects:@"C0", @"C1", @"C2", nil]) { CGFloat height = [[tableView dequeueReusableCellWithIdentifier:reusableIdentifier] bounds].size.height; hts[reusableIdentifier] = [NSNumber numberWithFloat:height]; } heights = [hts copy]; } NSString* prototype = [self _reusableIdentifierForIndexPath:indexPath]; return [heights[prototype] floatValue]; } - (NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return 3; } - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 1; } - (UITableViewCell*) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { NSString* prototype = [self _reusableIdentifierForIndexPath:indexPath]; UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:prototype]; return cell; } @end </code></pre>
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