How does one add UIButton to UIToolBar programmatically?

Question

I have added the toolbar using Interface Builder, but I need to add the buttons at runtime / conditionally. I'm not getting any errors, but my dynamic buttons are not appearing on the toolbar. I have verified that arrayOfModulesScreens is loaded with the data I need. At least that works (:)). Do I need to add the buttons into a UIView, then add that view to the toolbar? Just thinking outloud. Perhaps there is a better approach to begin with? Thanks in advance for any clues leading to the resolve.

CustomFormController.h

@interface CustomFormController : UIViewController { 
    UIToolbar *screensBar;  
}

CustomFormController.m

EPData *epData = [[EPData alloc] init];
NSArray *screens = [epData loadPlistIntoArray:@"Screens"];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"process_module_id == %@", process_modulesID];
NSArray *arrayOfModulesScreens = [screens filteredArrayUsingPredicate:predicate];

for(int i=0; i < [arrayOfModulesScreens count]; i++) {
    NSDictionary *dictRow = [arrayOfModulesScreens objectAtIndex:i];
    UIButton *button = [[UIButton buttonWithType:UIButtonTypeRoundedRect] retain];
    [button setTitle:[dictRow objectForKey:@"screen_title"] forState:UIControlStateNormal];
    [button addTarget:self action:@selector(buttonClick:) forControlEvents:UIControlEventTouchUpInside];
    [screensBar addSubview:button];  
}

Answer 1

If you are actually wanting to add a UIBarButtonItem (not a UIButton) to the toolbar, you just create one or more UIBarButtonItems, put them in an NSArray (or NSMutableArray), and assign that array to the items property of the toolbar. See the UIBarButtonItem documentation for details. Using your code above, that might look something like this:

    NSMutableArray *items = [NSMutableArray array];
    for (int i = 0; i < [arrayOfModulesScreens count]; i++) {
        NSDictionary *dictRow = [arrayOfModulesScreens objectAtIndex:i];
        UIBarButtonItem *button = [[UIBarButtonItem alloc] initWithTitle:[dictRow objectForKey:@"screen_title"]
                                                                   style:UIBarButtonItemStyleBordered
                                                                  target:self
                                                                  action:@selector(buttonClick:)];
        [items addObject:button];
        [button release];
    }
    screensBar.items = items;

(you would, of course, then need to change your buttonClick: to expect a UIBarButtonItem instead of a UIButton).

If you're really wanting to put a UIButton in there, you first need to wrap the UIButton in a UIBarButtonItem, something like this:

UIBarButtonItem *item = [[[UIBarButtonItem alloc] initWithCustomView:button] autorelease];

Then add the item to the toolbar as above.

---

As for why your buttons aren't showing up in your posted code, the problem is that UIButton's buttonWithType: creates a button with zero width and zero height. You would need to resize the button (manually or by using sizeToFit after setting the title) to make it show. After fixing that, you would then see that the buttons are all on top of each other in the upper-left corner of the parent view; you would need to position them manually as appropriate.