Answers to questions.

Answers to questions.

//(1) Ответы на первый вопрос.

@interface Foo : SomeObject
{
 NSString *_bar;
}

@property (retain) NSString *bar;
+ (id)foo;
@end


@implementation Foo

@synthesize bar = _bar;


- (NSString *)bar
{
    return _bar;
}


- (void)setBar:(NSString *)bar
{
    if (bar != _bar) {
        [bar retain];
        [_bar release];
        _bar = bar;
    }
}



// Update, тут все верно
+ (id)foo
{
   Foo *foo = [Foo alloc];
   [foo init];
   return [foo autorelease];
}



- (void)dealloc
{
    [_bar release]; // add release
    self.bar = nil;
    [super dealloc];
}

//(2) Ответы на 2-ой вопрос.
- (void)generateBlocks
{
    int i = 0;
    
    dispatch_block_t blockA = [^{   // добавили copy
        NSLog(@"i == %d", ++i);
    } copy];
    
    __weak Test *weakSelf = self; // добавили __weak
    dispatch_block_t blockB = [^{
        NSLog(@"self.i == %d", weakSelf.i);
    } copy];
    
    dispatch_block_t blockC = [^{
        NSLog(@"Hello from blockC!");
    } copy];
    
    self.blocks = @[blockA, blockB, blockC];
}


- (void)dealloc
{
    self.blocks = nil;
    [super dealloc];
}


// Ответ на 3 вопрос.
// Я не поклонник NSThread и performSelectorInBackgroung.
// поэтому попробую предложить вариант решений с GCD.

// код взял из BlocksKit.
#import "NSTimer+BlocksKit.h"

@interface NSTimer (BlocksKitPrivate)
+ (void)bk_executeBlockFromTimer:(NSTimer *)aTimer;
@end

@implementation NSTimer (BlocksKit)

+ (id)scheduledTimerWithTimeInterval:(NSTimeInterval)inTimeInterval block:(BKTimerBlock)block repeats:(BOOL)inRepeats 
{
	NSParameterAssert(block);
	return [self scheduledTimerWithTimeInterval: inTimeInterval
                                         target: self
                                       selector: @selector(bk_executeBlockFromTimer:)
                                       userInfo: [block copy]
                                        repeats: inRepeats];
}

+ (void)bk_executeBlockFromTimer:(NSTimer *)aTimer 
{
	 BKTimerBlock block = [aTimer userInfo];
	 if (block) block(aTimer);
}

@end

........
- (void)start
{
    self.timer = [NSTimer scheduledTimerWithTimeInterval:10.0f
                                      block:^(NSTimer *aTimer){
                             
                                           dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
 						NSLog(@"User info: %f", [aTimer timeInterval]);
                                           });
                                      }
                                    repeats:YES];
}
........

Comments are welcome!