create uibutton subclass

Question

I tried to subclass UIButton to include an activity indicator, but when i use initWithFrame:(since i'm subclassing uibutton i'm not using buttonWithType:) the button doesn't display. Also how would i set the button type in this case?:

my view controller:

    ActivityIndicatorButton *button = [[ActivityIndicatorButton alloc] initWithFrame:CGRectMake(10, 10, 300, 44)];
    [button addTarget:self action:@selector(buttonPressed) forControlEvents:UIControlEventTouchUpInside];
    [button setTitle:@"Older Posts..." forState: UIControlStateNormal];
    [cell addSubview:button];
    [button release];

my activityindicatorbutton class:

#import <Foundation/Foundation.h>


@interface ActivityIndicatorButton : UIButton {

    UIActivityIndicatorView *_activityView;
}

-(void)startAnimating;
-(void)stopAnimating;
@end

@implementation ActivityIndicatorButton

- (id)initWithFrame:(CGRect)frame {
    if (self=[super initWithFrame:frame]) {
        _activityView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
        _activityView.frame = CGRectOffset(_activityView.frame, 60.0f, 10.0f);

        [self addSubview: _activityView];
    }
    return self;
}

-(void) dealloc{
    [super dealloc];
    [_activityView release];
    _activityView = nil;
}

-(void)startAnimating {
    [_activityView startAnimating];
}

-(void)stopAnimating {
    [_activityView stopAnimating];
}
@end

Answer 1

Favour composition over inheritance.

Create a UIView which contains the components you need and add them to your view.

Answer 2

I ran into a similar situation, and agree with Jeff that you don't really need to subclass UIButton. I solved this by subclassing UIControl, and then overriding layoutSubviews to do all of the configuration of the views I wanted on my "button". It's a much more simple implementation that subclassing UIButton since there does seem to be some hidden mojo going on under the hood. My implementation looked like this:

- (id)initWithFrame:(CGRect)frame {
    self = [super initWithFrame:frame];
    if (self) {
    self.opaque = YES;

    self.imageView = [[UIImageView alloc] initWithFrame:CGRectZero];
    [self addSubview:self.imageView];

    self.textLabel = [[UILabel alloc] initWithFrame:CGRectZero];
    [self addSubview:self.textLabel];
    }

return self;
}

And layoutSubviews looked like this:

- (void)layoutSubviews {
[super layoutSubviews];

// Get the size of the button
CGRect bounds = self.bounds;

// Configure the subviews of the "button"
...
}