How to call a method from another view controller

Question

I am trying to figure out how to take the -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath; , method and call it from another view controller.

In LocationViewController.m

- (void)viewDidLoad {
  [super viewDidLoad];
  //save bar button item
  UIBarButtonItem *saveButton = [[UIBarButtonItem alloc] initWithTitle: @"Save" style: UIBarButtonItemStylePlain target: self action: @selector(saveButtonPressed)];

  self.navigationItem.rightBarButtonItem = saveButton;

  [self performSelector:@selector(saveButtonPressed) withObject:nil afterDelay:0.25];
}

-(void)saveButtonPressed {

    //I want to call the method here

}

In GameDetailsTableViewController.m

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

    static NSString *CellIdentifer1 = @"GameDetailsLocationCell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifer1];

    cell.textLabel.text = @"hello world"

    return cell;
}

I am a beginner in IOS and I would greatly appreciate any help.

Answer 1

You cannot call cellForRowAtIndexPath , but you can trigger the datasource methods of tableview from another class. Heres how

Suppose you want to trigger cellForRowAtIndexPath of Class A from Class B's method someMethod

In Class Am

-(void)viewDidLoad{
[[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(somemethodToReloadtableview) name:@"NOTIFICATIONNAME" object:nil];
}
//Implement the method
-(void)somemethodToReloadtableview{
[self.customTableViewName reloadData];
}

Class Bm

-(void)methodFromWhichYouWantToTrigger{
 [[NSNotificationCenter defaultCenter]postNotificationName:@"NOTIFICATIONNAME" object:nil];
}

PS - This method will invoke all the datasource of tableview such as numberOfRows . Hope this helps

Answer 2

I am not sure why you want to call the tableView: cellForRowAtIndexPath: manually. If you want your table view to reload the data, you can call reloadData method on your table view.

[yourTableView reloadData];

And if you want to trigger this from another view controller, you can post a notification from the other view controller and listen to that from the one where table view exists. Saheb's answer describes how to post the notification and listen to that.