Question

I would like to associate a sound effect when pressing down a uibutton. So far i have associate a method to the touch down event

 [allButton addTarget:self action:@selector(showAll) forControlEvents:UIControlEventTouchDownInside];

and call the play sound method within the method called:

 - (void)showAll
{
    [self.buttonSoundEffect play];

    ...
}

Is there a better way to do this? Can I subclass the UIButton class to handle the sound effect and refer to this new UIButton class for each button specific to my app?

Answer 1

I believe creating a category is the way to go.

I proceed this way:

.h:

#import <UIKit/UIKit.h>

@class SCLSoundEffect;

typedef enum {
  SCLCLICKSOUND = 0,
  SCLOTHERSOUND,  
} SCLSoundCategory;


@interface UIButton (soundEffect)

@property (nonatomic, strong) SCLSoundEffect *buttonSoundEffect;


+ (id) buttonWithType:(UIButtonType)buttonType andSound: (SCLSoundCategory)soundCategory;
- (void) playSound;

@end

.m:

#import "UIButton+soundEffect.h"
#import <objc/runtime.h>
#import "SCLSoundEffect.h"

static char const * const kButtonSoundEffectKey = "buttonSoundEffect";

@implementation UIButton (soundEffect)

@dynamic buttonSoundEffect;


+ (id) buttonWithType:(UIButtonType)buttonType andSound:(SCLSoundCategory) soundCategory;
{
    UIButton *newButton = [UIButton buttonWithType:buttonType];

    NSString *stringToUse = nil;

    switch (soundCategory) {
        case SCLCLICKSOUND:
            stringToUse = @"button_sound.wav";
            break;
        case SCLOTHERSOUND:
            assert(0); // To be defined

        default:
            break;
    }

    [newButton setButtonSoundEffect: [[SCLSoundEffect alloc] initWithSoundNamed:stringToUse]];
    [newButton addTarget:newButton action:@selector(playSound) forControlEvents:UIControlEventTouchDown];

    return newButton;
}


- (void) playSound
{
    [self.buttonSoundEffect play];
}


- (SCLSoundEffect *)buttonSoundEffect {
    return objc_getAssociatedObject(self, kButtonSoundEffectKey);
}

- (void)setButtonSoundEffect:(SCLSoundEffect *)buttonSoundEffect{
    objc_setAssociatedObject(self, kButtonSoundEffectKey, buttonSoundEffect, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (void) dealloc
{
    [self setButtonSoundEffect:nil];
}

Now each time I create a button that play some sound I just need to use the following method:

UIButton *mySoundButton = [UIButton buttonWithType:UIButtonTypeCustom andSound:SCLCLICKSOUND];