Question

My application is navigation base , I have two Table ViewControllers ,I am selecting data from second tableview and updating to details label of first tabaleview. The following code i am tried but not updating , I am getting secondtableview value in “Updatetableviewlable” method but i am not updating “cellForRowAtIndexPath” method, where i am doing mistake .. please any one guide me .

     @class First;

            @interface FertilityAppAppDelegate 


                First *firstObj;

            @property (nonatomic,retain) First *firstObj;

            @implementation FertilityAppAppDelegate
            @synthesize firstObj;


> didFinishLaunchingWithOptions


 //code 1
//  Updating detail view from second tableview to first tableview .


        firstObj= [[First alloc] initWithNibName:  @"First" bundle:nil];
        UINavigationController *aNavigationController = [[UINavigationController alloc]   initWithRootViewController: firstObj];
        self.navigationController = aNavigationController;
        [window addSubview:navigationController.view];
        [window makeKeyAndVisible];
        return YES;
 //code 2
// Not Updating detail view from second tableview to first tableview

      mainmenuObj = [[Mainmenu alloc] initWithNibName:@"Mainmenu" bundle:nil];
        firstObj= [[First alloc] initWithNibName:  @"First" bundle:nil];
        UINavigationController *aNavigationController = [[UINavigationController alloc]   initWithRootViewController: mainmenuObj];
        self.navigationController = aNavigationController;
        [window addSubview:navigationController.view];
        [window makeKeyAndVisible];
        return YES;         


        @interface First 
                 NSString *symptomlabel; FertilityAppAppDelegate *Appdelegate;
         @property (nonatomic,retain) NSString *symptomlabel    
        @implementation First
            @synthesize symptomlabel;


            - (void)viewDidLoad
            { 
                Appdelegate = (FertilityAppAppDelegate*)[[UIApplication sharedApplication] delegate];


            }

            -(void) Updatetableviewlable:(NSString*)lable
            {
                symptomlabel=[lable retain] ;
                NSLog(@"the update value is  %@", lable);


            }
            - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath
    *)indexPath 
        {
            static NSString *cellId = @"CellId";

            UITableViewCell *cell = (UITableViewCell*)[tableView dequeueReusableCellWithIdentifier:cellId];
            if (cell == nil) 
            {
                cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellId] autorelease];
                cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;   
            }
            switch (indexPath.section) 
            {
                case 0:
                {   
                    cell.textLabel.text = [self.MenstruationtoWakingArray objectAtIndex:indexPath.row];

                    if(indexPath.row==0)
                    {
                        UILabel *myLabel = [[UILabel alloc] initWithFrame:CGRectMake(160, 25, 125, 15)];
                        myLabel.text =symptomlabel;
                        myLabel.backgroundColor = [UIColor clearColor];
                        myLabel.textColor=[UIColor blueColor];
                        [self.tableView addSubview:myLabel];
                        NSLog(@"The Save file is:%@",symptomlabel);


                    }                    
                //statement case upto 10        
                }
        }           
        }
            @interface Second : UITableViewController 

            {


                FertilityAppAppDelegate *appDelegate;
            }


             @implementation Second tableview

                                viewDidLoad 

                                appDelegate = (FertilityAppAppDelegate
    *)[[UIApplication sharedApplication] delegate];


            - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath
    *)indexPath
            {
             if(indexPath.section==0)
             {     
              if (indexPath.row==0)
              {       
                NSString *updatelable =@"None";
                [appDelegate.firstObj Updatetableviewlable:updatelable];
                 appDelegate.selectedRow =indexPath.row;
              }
              //statement upto row 5

             }
                [self.tableView reloadData]; 
            }

Answer 1

In your Updatetableviewlable: method, you are assigning lable to symptomlabel. In this case, the symptomlabel may not retain the string lable. You try having Updatetableviewlable: method like this.

- (void)Updatetableviewlable:(NSString*)lable {

    symptomlabel = [lable retain];
    NSLog(@"%@", symptomlabel);
}

And make sure your cellForRowAtIndexPath: method looks something like this.

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    ...

    UILabel *myLabel;

    if (cell == nil) {

        myLabel = [[UILabel alloc] initWithFrame:CGRectMake(160, 25, 125, 15)];
        myLabel.backgroundColor = [UIColor clearColor];
        myLabel.textColor=[UIColor blueColor];
        myLabel.text = symptomlabel;
        [myLabel setTag:1];
        [cell.contentView addSubview:myLabel];
        [myLabel release];

    } else {

        myLabel = [[cell contentView] viewWithTag:1];
        myLabel.text = symptomlabel;
    }

    ...
}

Add also make sure you are reloading the table view in viewWillAppear: method of your First.m.

- (void)viewWillAppear:(BOOL)animated { 

    [[self tableView] reloadData]; 
}