Question

I am trying to create an iPhone app that creates a UIButton for every item in a NSArray. So basically, if there are 20 items in the array, 20 UIButtons are created, each with an identifier that somehow connects it to the respective item in the array. If I were to add another item to the array, 21 buttons would be created instead of 20. Is there a way to do this using Storyboards and Interface Builder?

Also, is there a way to paginate the UIButtons that are created? I want to have six buttons on a screen, with the option of scrolling to the next 6. So if there are 20 items in the array, it would create a ScrollView with 6 on the first 3 pages and 2 on the last one.

Thanks ahead of time! I’m trying to avoid using a TableView for this for visual reasons. If there’s an easier way to accomplish this, please let me know!

Answer 1

In my opinion, this wouldn’t be easy using InterfaceBuilder. You better create them using code. For the pagination, you have to use a paging UIScrollView.

#define BUTTON_WIDTH 40
#define BUTTON_HEIGHT 30
#define BUTTON_PADDING 10
#define BUTTONS_PER_PAGE 6
#define PAGE_WIDTH ((BUTTON_WIDTH + BUTTON_PADDING) * BUTTONS_PER_PAGE)
#define MAGIC_BUTTON_TAG_OFFSET 6238 /* Maybe somebody already uses views with tags like 0, 1, 2, 3...)

// in an init... method:

UIScrollView *sv = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 80, 320, 320)];
sv.contentSize = CGSizeMake(PAGE_WIDTH, sv.frame.size.height);
sv.pagingEnabled = YES;
[self.view addSubview:sv]; // assuming a view controller

NSArray *a = [NSArray arrayWithObjects:...]; // whatever

for (int i = 0; i < a.count; i++)
{
    UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    btn.frame = CGRectMake(i * (BUTTON_WIDTH + BUTTON_PADDING), 0, BUTTON_WIDTH, BUTTON_HEIGHT);
    btn.tag = i + MAGIC_BUTTON_TAG_OFFSET; // to relate to the array index
    [btn setTitle:[NSString stringWithFormat:@"Button No. %d", i] forState:UIControlStateNormal];
    [btn addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [sv addSubview:btn];
}

- (void)buttonPressed:(UIButton *)btn
{
    int index = btn.tag - MAGIC_BUTTON_TAG_OFFSET;
    id object = [a objectAtIndex:index];

    [self doSomethingWithObject:object];
}

Hope this helps.