Call [tableView reloadData]; on a viewController from a modalViewController

Question

I have a modalViewController that comes up over the top of a viewController with a tableView. When the user clicks a button on the modalViewController I want to reload the tableView within the viewController with this:

[tableView1 reloadData];

I do not want to put the reload in the viewDidAppear or viewWillAppear methods as they get called when i do not need the tableView to reload (i.e. when the user clicks the back button to return to the tableView).

Is there a way to do this?

Hi Anil, Im not exactly sure how to do that. Do you have any examples or recommendations for getting started? — Brandon, Mar 04 '13 at 05:33
@Brandon Go for Delegate. That will be really helpful to you. — βhargavḯ, Mar 04 '13 at 05:41
thanks @Bhargavi - Im not actually sure what that means or how to do it. Can you give me any pointers? — Brandon, Mar 04 '13 at 05:44
Look at this http://stackoverflow.com/questions/6168919/how-do-i-set-up-a-simple-delegate-to-communicate-between-two-view-controllers — Anil Kothari, Mar 04 '13 at 05:44
Yes follow steps given in link by Anil . And implement delegate method in your ViewController with reloadData. — βhargavḯ, Mar 04 '13 at 05:49

score 2 · Answer 1 · answered Mar 04 '13 at 05:33

2

Try

1) write one method which reloads the table data.

2) Call it on the back button clicked.

answered Mar 04 '13 at 05:33

Girish

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Hi Girish, I have the method built. I want to call it when the user clicks a button on a modal view, not the back button. Do you know how to go about doing this? – Brandon Mar 04 '13 at 05:34
i believe Girish means create your reload method inside the viewcontroller (that has your tableview) and call that from the modalviewcontroller – John Riselvato Mar 04 '13 at 05:36
In that case create one delegate which automatically calls when you clicked the button. – Girish Mar 04 '13 at 05:36
@JohnRiselvato you are right but if he did not want this, then used delegate as I mentioned in previous comment. – Girish Mar 04 '13 at 05:37
@JohnRiselvato I guess I just don't know how to call a method on one viewController from another – Brandon Mar 04 '13 at 05:41
@Brandon call the method using the object of view controller as [vc reloadTableDate]; as vc is the obj of view controller. – Girish Mar 04 '13 at 05:47

score 2 · Answer 2 · answered Mar 04 '13 at 05:57

This is the classic delegate pattern problem, in your modal view controller you need a delegate reference to the current view controller presenting it

//Modal
@protocol ModalVCDelegate
- (void)tappedBackButton;
@end

@class ModalVC: UIViewController
@property id<ModalVCDelegate> delegate;
@end

@implementation
- (void)backButtonTapped:(id)sender
{
    if (self.delegate) 
        [self.delegate tappedBackButton];
}
@end

Now, in your presenting VC, just process this delegate message

//Parent VC
- (void)showModal
{
    ModalVC *vc = [ModalVC new]; 
    vc.delegate = self;
    //push
}

- (void)tappedBackButton
{
    [self.tableView reloadData];
    //close modal
}

score 1 · Answer 3 · edited May 23 '17 at 12:12

1

You can use delegate . If find it more harder then alternative is to use NSNotificationCenter. You can see accepted answer for Refreshing TableView. This is really very short, easy and understandable way.

edited May 23 '17 at 12:12

Community

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1

answered Mar 04 '13 at 05:55

βhargavḯ

9,786
1
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59

score 0 · Answer 4 · answered Mar 04 '13 at 05:52

0

Try to use this one

Make a Button and click on this button and than you can reload your data. This button make custom and use it on background.

  - (IBAction)reloadData:(id)sender
    {
         [tblView reloadData];
    }

answered Mar 04 '13 at 05:52

Dharmbir Singh

17,485
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score 0 · Accepted Answer · answered Mar 04 '13 at 05:52

using Notification like bellow Method:-

Create NSNotificationCenter at yourViewController's ViewdidLoad Mehod

- (void)viewDidLoad
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(ReloadDataFunction:)
                                                     name:@"refresh"
                                                   object:nil];

  [super viewDidLoad];

}
-(void)ReloadDataFunction:(NSNotification *)notification {

    [yourTableView reloadData];

}

Now you can Call this Notification from your modelViewController BackButton or else you want from calling this Refresh notification like putting this line of code:-

[[NSNotificationCenter defaultCenter] postNotificationName:@"refresh" object:self];

NOTE: postNotificationName:@"refresh" this is a key of particular Notification

score -2 · Answer 6 · answered Mar 04 '13 at 06:01

You can use NSNotification to refresh table on ViewController.

Inside viewController :

-(void)dealloc{
[[NSNotificationCenter defaultCenter] removeObserver:self];
[super dealloc];
}

Write code in viewDidLoad:
[[NSNotificationCenter defaultCenter] addObserver:self
        selector:@selector(reloadMainTable:) 
        name:@"ReloadTable"
        object:nil];




- (void) reloadMainTable:(NSNotification *) notification
{
  [tableView reload];
}


Inside ModelViewController:
[[NSNotificationCenter defaultCenter] 
        postNotificationName:@"ReloadTable" 
        object:nil];

Here you can also send custom object instead of nil parameter. But be care full about removal of NSNotification observer.

Hello can any one tell me? – Sudesh Kumar Mar 04 '13 at 06:14 — Sudesh Kumar, Mar 04 '13 at 06:14

Call [tableView reloadData]; on a viewController from a modalViewController

6 Answers6

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