After converting to ARC I am getting "message sent to deallocated instance"

Question

I am creatinng an instance of a View like this...

- (IBAction)findPatientTapped:(id)sender { 

    RequestDialogViewController *findPatientViewController = [[RequestDialogViewController alloc] initWithNibName:@"RequestDialogViewController"    bundle:nil];

    findPatientViewController.delegate = self;
    findPatientViewController.autoCorrectOff = YES;
    findPatientViewController.defaultResponse = @"";
    findPatientViewController.keyboardType = @"ASCII";
    findPatientViewController.returnKeyType = @"Go";
    findPatientViewController.tag = findRequestTag;
    findPatientViewController.editSet = YES;
    findPatientViewController.titleText = @"Find Patient";
    findPatientViewController.messageText =@"Enter all or a portion of the patient's name...";
    findPatientViewController.messageText2 = @"Last Name...";
    findPatientViewController.messageText3 = @"First Name...";
    findPatientViewController.showResponse2 = YES;   
    findPatientViewController.showNavBarSaveButton = NO;
    findPatientViewController.infoTextFile = @"";
    findPatientViewController.view.frame = CGRectMake(280, 230, 480, 300);

    [self.view addSubview:findPatientViewController.view];
}

The view contains 2 UITextField fields for entry by the user. This all worked fine before running the convert to ARC tool. After the conversion the view crashes when trying to enter a value in either of the 2 fields with...

-[RequestDialogViewController respondsToSelector:]: message sent to deallocated instance

Here is the .h file of the UIViewController after running the conversion to ARC tool...

#import <UIKit/UIKit.h>
@protocol RequestDialogViewControllerDelegate;

@interface RequestDialogViewController : UIViewController <UITextFieldDelegate>{
    id<RequestDialogViewControllerDelegate> __weak delegate;
    IBOutlet UINavigationBar *navBar;
    IBOutlet UITextField *response;
    IBOutlet UITextField *response2;
    IBOutlet UILabel *message;
    IBOutlet UILabel *message2;
    IBOutlet UILabel *message3;
    IBOutlet UIButton *saveButton;
    NSTimer *selectAllTimer;

    NSString *defaultResponse;
    NSString *titleText, *infoTextFile;
    NSString *messageText, *messageText2, *messageText3;
    NSString *placeHolderText;
    NSString *keyboardType, *returnKeyType;
    BOOL editSet, showSaveButton,showNavBarSaveButton, showResponse2, autoCorrectOff;
    int tag;
}

@property (weak) id<RequestDialogViewControllerDelegate> delegate;
@property (nonatomic, strong)IBOutlet UITextField *response;
@property (nonatomic, strong) IBOutlet UITextField *response2;
@property (nonatomic, strong)IBOutlet UILabel *message;
@property (nonatomic, strong)IBOutlet UILabel *message2;
@property (nonatomic, strong) IBOutlet UILabel *message3;
@property (nonatomic, strong)IBOutlet UIButton *saveButton;
@property (nonatomic, strong)NSString *defaultResponse;
@property (nonatomic, strong)NSString *titleText, *infoTextFile;
@property (nonatomic, strong)NSString *messageText, *messageText2, *messageText3;
@property (nonatomic, strong)NSString *placeHolderText;
@property (nonatomic, strong)NSString *keyboardType, *returnKeyType;
@property (nonatomic, strong)IBOutlet UINavigationBar *navBar;
@property (readwrite)BOOL editSet, showSaveButton, showNavBarSaveButton, showResponse2, autoCorrectOff;
@property (readwrite)int tag;
@property (nonatomic, strong) NSTimer *selectAllTimer;

- (IBAction)saveButtonPressed:(id)sender;
- (void)selectAll;
- (IBAction)editingDidEnd:(id)sender;

@end


@protocol RequestDialogViewControllerDelegate <NSObject>
@optional
- (void)requestDialogViewDidDismiss:(RequestDialogViewController *)controller withResponse:(NSString*)reqResponse response2:(NSString*)reqResponse2;
@end

Here is the pertenant references in the .h file of the class creating the instance of the RequestDialog view...

#import "RequestDialogViewController.h"

@interface OrthoViewController : UIViewController <RequestDialogViewControllerDelegate>{
}
- (void)requestDialogViewDidDismiss:(RequestDialogViewController *)controller withResponse:(NSString*)reqResponse response2:(NSString*)reqResponse2;
@end

What do I need to do to make this work under ARC? I am thinking it might have something to do with how the protocol is formed.

Thanks,

John

**** Thanks to Dan I resolved this by making findPatientViewController a property of the calling class...

RequestDialogViewController *findPatientViewController;
@implementation OrthoViewController

- (IBAction)findPatientTapped:(id)sender {    
    findPatientViewController = [[RequestDialogViewController alloc] initWithNibName:@"RequestDialogViewController" bundle:nil];
    //set all the properties and add the subview
 }
@end

Answer 1

Your findPatientViewController has nothing retaining it, so it gets deallocated at the end of the method where you create it. Then, when something in it's view tries to call a delegate method on it you get that crash.

If findPatientTapped is a method in a view controller then you should add the findPatientViewController as a child view controller. If it's in a view, then you need to least store the findPatientViewController in a property so it doesn't get deallocated while you are still using it.

Your code didn't really work properly before ARC, you just had a memory leak.