iOS : How to reference a music background from a singleton class?

问题

I have done a singleton class called MyBgMusic.h & MyBgMusic.m. How to reference that singleton class to my SecondViewController or the rest of the XIB.

Here is my singleton class:

H file :

#import <Foundation/Foundation.h>
#import <AVFoundation/AVAudioPlayer.h>

@interface MyBgMusic : UIViewController <AVAudioPlayerDelegate> {


    AVAudioPlayer *player;
    UIButton *playBgMusic;


}

@property (nonatomic, retain) IBOutlet AVAudioPlayer *player;
@property (nonatomic, retain) IBOutlet UIButton *playBgMusic;


+ (id)sharedManager;

-(IBAction) toggleMusic;


@end

M file :

#import "MyBgMusic.h"

static MyBgMusic *sharedMyManager = nil;

@implementation MyBgMusic

@synthesize player,playBgMusic;

#pragma mark -
#pragma mark Singleton Methods

+ (MyBgMusic*)sharedManager {

    static MyBgMusic *sharedMyManager;
    if(!sharedMyManager) {
        static dispatch_once_t oncePredicate;
        dispatch_once(&oncePredicate, ^{
            sharedMyManager = [[super allocWithZone:nil] init];
            });
        }

        return sharedMyManager;
}

+ (id)allocWithZone:(NSZone *)zone {    

    return [self sharedManager];
}


- (id)copyWithZone:(NSZone *)zone {
    return self;    
}

#if (!__has_feature(objc_arc))

- (id)retain {  

    return self;    
}

- (unsigned)retainCount {
    return UINT_MAX;  //denotes an object that cannot be released
}


- (id)autorelease {

    return self;    
}

- (void)dealloc
{
    [MyBgMusic release];
    [playBgMusic release];
    [player release];
    [super dealloc];
}
#endif

#pragma mark -
#pragma mark Custom Methods

- (IBAction)toggleMusic {

    if ([self.player isPlaying] == YES) {
        [self.player stop]; 
    } else {
        [self.player play];
    }
    self.playBgMusic.enabled = YES;

}

- (void)viewDidLoad
{

    NSString *path = [[NSBundle mainBundle] pathForResource:@"music" ofType:@"mp3"];
    self.player=[[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL]; 
    player.delegate = self;
    [player play];
    player.numberOfLoops = -1;
    [super viewDidLoad];

    // Do any additional setup after loading the view from its nib.
}

SecondViewController.m ( I want to reference from the singleton class so that I can use it all over again without mess up the background music when pressing on and off. )

- (IBAction)toggleMusic{

    if ([self.player isPlaying] == YES) {
        [self.player stop]; 
    } else {
        [self.player play];
    }
    self.playBgMusic.enabled = YES;

}

Should I declare like this :

-(IBAction) sharedMusic {

    [[MyBgMusic sharedManager] toggleMusic]; // instance method shareManager not found. What does it mean?

}

回答1:

Create an IBAction in your SecondViewController hook up the xib then in code then have it call

[[MyBgMusic sharedInstance] toggleMusic];

回答2:

In SecondViewController you should call [[MyBgMusic sharedInstance] toggleMusic];in the IBAction when you want to toggle music. Just as you used self.player.

回答3:

You have to import your class and reference it wherever you want using this line :

[[MyBgMusic sharedManager] toggleMusic]

If you want, you can add even property and reference it without create an instance of your class.

来源：https://stackoverflow.com/questions/8455576/ios-how-to-reference-a-music-background-from-a-singleton-class

标签

iphone

objective-c

singleton