performeguewithidentifier在IBAction方法中不起作用

Question

I have a storyboard with a segue connected between to views and the following code. For some reason the segue isn't being called and I am positive it is named correctly. I am wondering if it dosen't work because it is in an IBAction method or what. I am very confused so let me know if you have any ideas. thanks.

-(IBAction)didPressSubmit:(id)sender{

    NSString *idOfObject = [[NSUserDefaults standardUserDefaults] objectForKey:@"idOfObject"];


    PFQuery *query = [PFQuery queryWithClassName:@"RequestsClass"];


    [query getObjectInBackgroundWithId:idOfObject block:^(PFObject *myObj, NSError *error) {

        myObj[@"hasResponded"] = @"has";
        myObj[@"answer"] = textField.text;
        [myObj saveInBackground];



    }];

        [self performSegueWithIdentifier:@"userDidRespond" sender:self];
}

Also there are no errors just nothing happens. I added an NSLog right above the line that calls it saying "about to perform segue" and it printed fine. So I'm not sure.

I am also getting this warning

Warning: A long-running Parse operation is being executed on the main thread. 
 Break on warnParseOperationOnMainThread() to debug

So i maybe i need to Deque main thread or something like that? Thanks

Answer 1

Move this line :

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

inside the block.

Like this :

-(IBAction)didPressSubmit:(id)sender{

NSString *idOfObject = [[NSUserDefaults standardUserDefaults] objectForKey:@"idOfObject"];


PFQuery *query = [PFQuery queryWithClassName:@"RequestsClass"];


[query getObjectInBackgroundWithId:idOfObject block:^(PFObject *myObj, NSError *error) {

    myObj[@"hasResponded"] = @"has";
    myObj[@"answer"] = textField.text;
    [myObj saveInBackground];

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

}];

}

I hope this will do the trick.

Answer 2

you can also navigate from one view controller to another by following code without using performSegueWithIdentifier method.

 UIStoryboard *story = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
 viewController *viewObj = [story instantiateViewControllerWithIdentifier:@"viewController"];

 [self.navigationController pushViewController:viewObj animated:YES];

For this you have to give storyboardID to viewcontroller as "viewController" in your storyboard. And by this method you can also set objects for next view.

Answer 3

The Parse warning you are getting is unrelated and should go in a different question. It is telling you that you are trying to connect to Parse (maybe a login in?) on the main thread. You want to do this asynchronously on a different thread with a completion block.

Something like this: (in SWIFT)

PFUser.logInWithUsernameInBackground(userName.text, password: passwordField.text, block: {
        (user,error) in
        completion(error == nil)
    })

Parse has many examples in Objective-C as well.