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    <p>There are MANY ways to do this, and over the time I've been working on iPhone software I've experimented with most of them. Here's one.</p> <p>In your child view controller, you can make a property that is a pointer to the parent view controller. Thusly:</p> <p>ChildViewController.h</p> <pre><code>#import "ParentViewController.h" @interface ChildViewController : UIViewController { ParentViewController *parentViewController; } @property (nonatomic, retain) ParentViewController *parentViewController; </code></pre> <p>ChildViewController.m</p> <pre><code>@implementation ChildViewController @synthesize parentViewController; -(void)dealloc { [parentViewController release]; } </code></pre> <p>When you do the work to instantiate the child and push it onto the nav controller, you can set any variables you want on that child's properties, including setting, say:</p> <pre><code>ChildViewController *child = [[ChildViewController alloc] initWithNib:@"nibName" withBundle:nil]; child.parentViewController = self; [self.navigationController pushViewController:child animated:YES]; [child release]; </code></pre> <p>Then inside the child, you can talk about properties of the parent directly, as they get set by the user in the fields of the child, so...</p> <pre><code>self.parentViewController.dataField = @"My data for an NSString property of the parent view controller!"; </code></pre> <p>Then when you pop the child back off, you'll find that you actually set that data into the <code>.dataField</code> property of the parent view controller.</p> <p>(All code in this answer was typed right in here and is intended as an example only--I make no promises about spelling, syntax, etc. )</p>
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    1. POObj-c, If I'm using getters and setters for a selection screen pushed into navigation, where do I get my value back, viewWillAppear?
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    1. USDan Ray
    1. USDan Ray
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    1. POObj-c, If I'm using getters and setters for a selection screen pushed into navigation, where do I get my value back, viewWillAppear?
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    1. CObut beware of circular references: parent retains child and child retains parent. You'll need extra precautions to break the loop, otherwise you'll get nasty leaks.
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      1. USAxel
    2. COWe're using a UINavigationController here, though, which will release the child when it pops it. And ParentViewController releases the child when it pushes it on the nav stack. So there's no circularity in this instance--though it's true that the most general application of this approach certainly could be prone to it. Just to be clear about that, I added the release on push to my sample code.
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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.

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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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