Question

I want is on main window to present the created modalViewController view when the infobutton is pressed. But when I press Info button on the main window nothing happens.

In the mainviewcontroller.h file I have following code:

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface imageviewViewController : UIViewController{
AVAudioPlayer *audioPlayer;
}

@property (nonatomic, retain) UIToolbar *toolbar;
@property (nonatomic, assign) UIBarButtonSystemItem currentSystemItem;
@property (nonatomic, retain) AVAudioPlayer *audioPlayer;

@end

In the mainviewcontroller.m file have following code:

#import "imageviewViewController.h"
#import "Infoviewcontroller.h"


@implementation imageviewViewController

@synthesize toolbar;
@synthesize currentSystemItem;
@synthesize audioPlayer;

UIBarButtonItem *infoItem = [[UIBarButtonItem alloc] 
                          initWithTitle:@"Info" 
                          style:UIBarButtonItemStyleBordered 
                          target:nil 
                          action:@selector(Infobuttonpressed)]; 

  // flex item used to put space in between buttons

    UIBarButtonItem *flexItem = [[UIBarButtonItem alloc] 
                             initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
                             target:nil
                             action:nil];

    //Add buttons to the array

    NSArray *toolbarItems = [NSArray arrayWithObjects: settingsButton, flexItem, systemItem, flexItem, systemItem1,flexItem, systemItem2, flexItem, systemItem3, flexItem, infoItem, nil];

     [toolbar setItems:toolbarItems];

    [settingsButton release];
    [systemItem  release];
    [systemItem1 release];
    [systemItem2 release];
    [systemItem3 release];
    [infoItem release];
    [flexItem release];

[super viewDidLoad];  

}


- (void) Infobuttonpressed: (id) sender
{
Infoviewcontroller *myView = [[Infoviewcontroller alloc] init];
[self presentModalViewController:myView animated:YES]; // present view modally
[self.navigationController pushViewController:myView animated:YES]; // add to navigation stack
[myView release];
}

In the Infoviewcontroller.h file have following code:

#import <UIKit/UIKit.h>

@interface Infoviewcontroller : UIViewController <UITextViewDelegate>

{

UITextView *textView;

}

@property (nonatomic, retain) UITextView *textView;
@property (nonatomic, assign) UINavigationBar *navBar;


@end

Then in the infoviewcontroller.m file have the following code:

#import "Infoviewcontroller.h"

@implementation Infoviewcontroller

@synthesize textView;
@synthesize navBar;



-(void)dealloc
{
[textView release];
    [navBar release];
[super dealloc];
}

 -(void)setupTextView
  {
self.textView = [[[UITextView alloc] initWithFrame:self.view.frame] autorelease];

self.textView.textColor = [UIColor redColor];

self.textView.font = [UIFont fontWithName:@"System Bold" size:13];

self.textView.delegate = self;

self.textView.backgroundColor = [UIColor whiteColor];

self.textView.textAlignment =  UITextAlignmentCenter;

self.textView.text = @"This is UITextView\nThis is UITextView\nThis is UITextView\nThis is UITextView"; 

[self.view addSubview: self.textView];    

}

- (void)viewDidLoad
{
[super viewDidLoad];

navBar = [[UINavigationBar alloc] init];
UINavigationItem *navItem = [[[UINavigationItem alloc] initWithTitle:@"ModalViewControllerTest"] autorelease];
UIBarButtonItem *done = [[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(dismissView:)] autorelease];
navItem.rightBarButtonItem = done;
navBar.items = [NSArray arrayWithObject:navItem];
[self.view addSubview:navBar];
}

Answer 1

UIBarButtonItem *infoItem = [[UIBarButtonItem alloc] 
                          initWithTitle:@"Info" 
                          style:UIBarButtonItemStyleBordered 
                          target:nil 
                          action:@selector(Infobuttonpressed)]; 

Should be

UIBarButtonItem *infoItem = [[UIBarButtonItem alloc] 
                          initWithTitle:@"Info" 
                          style:UIBarButtonItemStyleBordered 
                          target:self
                          action:@selector(Infobuttonpressed:)]; 

Spot the difference? First, you’re missing a target (should be self, not nil). Second, the colon at the end of the selector is part of the signature, you were missing it so it was not calling your method (which is InfoButtonPressed:(id)sender).

As an aside, methods should start with a lower case name.