xcode/ios: push view controller programatically and pass row info

Question

I have a table. When you click on row of table you get detail using prepare for segue. From detail page, I have an edit button that lets you open a view controller previously created in the storyboard modally.

The question is how can I pass the row of the detail item or otherwise give the edit controller the info of what item to display?

Here is code that launches view controller.

//create Edit navigation button:

 UIBarButtonItem *editButton = [[UIBarButtonItem alloc]
                                   initWithTitle:@"Edit"
                                   style:UIBarButtonItemStylePlain
                                   target:self
                                   action:
                                   //next line calls method editView
                                   @selector(editView:)];
    self.navigationItem.rightBarButtonItem = editButton;

//method that fires when you click button to launch edit view controller


- (void) editView:(id) sender
{
    NSLog(@"pressed");
    UIStoryboard *storyBoard = self.storyboard;
    NSString * storyboardName = [storyBoard valueForKey:@"name"];
    UIViewController *vc = [[UIStoryboard storyboardWithName:storyboardName bundle:nil] instantiateViewControllerWithIdentifier:@"editvc"];
    IDEditVC *secondViewController =
    [storyBoard instantiateViewControllerWithIdentifier:@"editvc"];
}

But how can I pass the information on the item to edit?

Thanks for any suggestions.

What do you mean by "previously created in the storyboard modally"? You're creating the controller in your editView method. You have a pointer (secondViewController) to it there, so you can pass any information you need in that method. It's not at all clear why you're instantiating 2 controllers, vc and secondViewController in editView, and you don't do anything with either of them. — rdelmar, Apr 05 '15 at 04:48
You can easily pass data to a view controller. Its upto you how you want data as an array or string. You define variables in the edit viewcontroller and pass the data from detail page. — Uttam Sinha, Apr 05 '15 at 07:12

BlackM · Accepted Answer · 2015-04-05T22:20:07.183

0

Lets assume that in UITableViewController you are building the TableView an array with objects(eg: MyObject.m/h). You should detect which cell the user has select using the didSelectRowAtIndexPath and then retrieve MyObject from your array using that integer at prepare for segue. Eg:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{

        cellPressed =(int)indexPath.row; //cellPressed is an integer variable(global variable in my VC

        [self performSegueWithIdentifier:@"toMyVC" sender:self];

}

Now on prepareForSegue:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

if([[segue identifier] isEqualToString:@"toMyVc"]){

    MyVC *mVC = [segue destinationViewController];
    mVC.myObject = [myArrayWithMyObjects objectAtIndex:cellPressed];

 }
}

In your Edit View:

IDEditVC *secondViewController =
[storyBoard instantiateViewControllerWithIdentifier:@"editvc"];
secondViewController.myObj = myObjectRetrievedFromArray;

Note: You should declare a variable MyObject in .h file in order to be visible from other classes.

Declaring a "global" variable in a class:

@interface ViewController : UIViewController{

  int cellPressed; //This is accessible by any method in YourViewController.m
}

edited Apr 05 '15 at 22:20

answered Apr 05 '15 at 10:36

BlackM

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Would this be the same using Core Data. In prepareforsegue I currently just have Items *item = [self.fetchedResultsController objectAtIndexPath:indexPath]; and then destViewController.item=item – user1904273 Apr 05 '15 at 17:44
Realized I do not know how to create a global variable. Do you use extern? – user1904273 Apr 05 '15 at 18:33
Do you create a new separate class for the global variable or do you just put it in some class that is imported into the view controllers I am working with such as the data model that holds the core data stuff? – user1904273 Apr 06 '15 at 14:50
In our case global variable for the class means that is a variable that it can be accessed by any method of the instance class. Not a global variable which can be accessed by any class. I declare it as I showed on the example in the .h of my class – BlackM Apr 06 '15 at 16:44
Not sure which class you put it in but I put it in model which is lazy loaded in all three VCs, tableview, detail and edit. However, I am having trouble storing Indexpath as integer. I created property to hold integer in edit vc with @property(assign,nonatomic) int *indexNum; Is this right syntax? secondViewController.indexNum = &(cellPressed); – user1904273 Apr 06 '15 at 18:49
Also, I can't seem to put int cellPressed; after interface in any of my objects. It says cannot put after interface. Does class have to be uiviewcontroller? – user1904273 Apr 06 '15 at 18:57
1

Okay, I was able to get it to work with answer from following question that is similar to yours...http://stackoverflow.com/questions/9016680/how-many-ways-to-pass-share-data-b-w-view-controller. Marking yours right cause it helped me out although I did it a somewhat different way based on link. Thanks. – user1904273 Apr 06 '15 at 19:30

xcode/ios: push view controller programatically and pass row info

1 Answers1