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copied!<p>As @trojanfoe said, delegation is a better way to do it. Instead of <code>#import "RootViewController.h"</code>, it is better to adop delegation. Because <code>UITableViewCell</code> is a child and <code>RootViewController</code> is the parent view. You don't want the child to talk <strong>directly</strong> with the parent.</p> <ul> <li><p>To adopt delegation:</p></li> <li><p>in <code>MyCell.h</code> file</p></li> <li><p>remove <code>#import "RootViewController.h"</code>.</p></li> <li><p>revise <code>MyCell.h</code> as follows:</p></li> </ul> <blockquote> <pre><code>@protocol MyCellDelegate; // if you need to have forward declaration @interface MyCell : UITableViewCell // @property (nonatomic, strong) IBOutlet RootViewController *rootViewController; @property (nonatomic) id <MyCellDelegate> delegate; @end @protocol MyCellDelegate <NSObject> - (void)refreshVisibleViewForCellTagged:(NSInteger)cellTag; @end </code></pre> </blockquote> <ul> <li>in <code>MyCell.m</code>.</li> </ul> <blockquote> <pre><code>@synthesize delegate; -(IBAction)checkBoxClicked:(UIButton*)sender { [self setCheckBoxChecked:!_checkBoxChecked]; //[_rootViewController refreshVisibleViewForCellTagged:self.tag]; [self.delegate refreshVisibleViewForCellTagged:self.tag]; } </code></pre> </blockquote> <ul> <li>in <code>RootViewController.h</code> adopt the delegation of MyCell</li> </ul> <blockquote> <pre><code>#import "MyCell.h" @interface RootViewController : UIViewController <MyCellDelegate> </code></pre> </blockquote> <ul> <li>in <code>RootViewController.m</code>.</li> </ul> <blockquote> <pre><code>- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { UITableViewCell *cell = // your implementation //assuming all your cells are of MyCell kind // set RootViewController as the delegate of each cell ((MyCell *)cell).delegate = self; return cell; } </code></pre> </blockquote> <ul> <li>implement the delegate method in <code>RootViewController.m</code>.</li> </ul> <blockquote> <pre><code>- (void)refreshVisibleViewForCellTagged:(NSInteger)cellTag { // whatever you have } </code></pre> </blockquote> <p>P.S. The above codes are for illustration. I didn't run them. If some part doesn't work, let me know, and I'll revise it.</p> <p>The reason those objects in RootViewController are nil in the way you call, is because you are not accessing the same instance of RootViewController. It is a different (new) instance and hence all objects are nil. </p>

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