Question

我正在尝试实现一个计时器，但我的访问权限很差......我没有在dealloc中使用release。

.h 

   NSTimer *_timerAnimacao;

@property (nonatomic, retain) NSTimer *timerAnimacao;

.m 
@synthesize timerAnimacao = _timerAnimacao;

这是我打电话给计时器的地方。

  if(acondition)
       _timerAnimacao = [NSTimer scheduledTimerWithTimeInterval:0.06 target:self selector:@selector(changeTimeFilter:) userInfo:nil repeats:YES];
     else 
            _timerAnimacao = [NSTimer scheduledTimerWithTimeInterval:0.06 target:self selector:@selector(changeTimeFilterHide:) userInfo:nil repeats:YES];

changeTimeFilter工作正常......但changeTimeFilterHide正在 BAD Access 。

-(void)changeTimeFilter:(NSTimer *)theTimer{

    if (tAnimacaoFilter<5) {
        [_tbFilters setFrame:CGRectMake(_tbFilters.frame.origin.x, _tbFilters.frame.origin.y, _tbFilters.frame.size.width, 58*tAnimacaoFilter)];
    }
    if(tAnimacaoFilter < 10) {
        tAnimacaoFilter++;
        [_tbFeeds setFrame:CGRectMake(_tbFeeds.frame.origin.x, _tbFeeds.frame.origin.y + (4.4*tAnimacaoFilter), _tbFeeds.frame.size.width, _tbFeeds.frame.size.height - (4.4*tAnimacaoFilter))];
        [imgBordaTbDireita setFrame:CGRectMake(imgBordaTbDireita.frame.origin.x, _tbFeeds.frame.origin.y - 4, imgBordaTbDireita.frame.size.width, imgBordaTbDireita.frame.size.height)];
        [imgBordaTbEsquerda setFrame:CGRectMake(imgBordaTbEsquerda.frame.origin.x, _tbFeeds.frame.origin.y, imgBordaTbEsquerda.frame.size.width, imgBordaTbEsquerda.frame.size.height)];
    }
    else {
        if(_timerAnimacao)
           [_timerAnimacao invalidate];
        [btnFilter setEnabled:YES];
    }
}

-(void)changeTimeFilterHide:(NSTimer *)theTimer{
    if (tAnimacaoFilter<5) {
        [_tbFilters setFrame:CGRectMake(_tbFilters.frame.origin.x, _tbFilters.frame.origin.y, _tbFilters.frame.size.width, (58*5) - (58*tAnimacaoFilter))];
    }
    if(tAnimacaoFilter < 10) {
        tAnimacaoFilter++;
        [_tbFeeds setFrame:CGRectMake(_tbFeeds.frame.origin.x, _tbFeeds.frame.origin.y - (4.4*tAnimacaoFilter), _tbFeeds.frame.size.width, _tbFeeds.frame.size.height + (4.4*tAnimacaoFilter))];
        [imgBordaTbDireita setFrame:CGRectMake(imgBordaTbDireita.frame.origin.x, _tbFeeds.frame.origin.y - 4, imgBordaTbDireita.frame.size.width, imgBordaTbDireita.frame.size.height)];
        [imgBordaTbEsquerda setFrame:CGRectMake(imgBordaTbEsquerda.frame.origin.x, _tbFeeds.frame.origin.y, imgBordaTbEsquerda.frame.size.width, imgBordaTbEsquerda.frame.size.height)];
    }

    else {
        if(_timerAnimacao)
            [_timerAnimacao invalidate];
        [btnFilter setEnabled:YES];
    }
}

Answer 1

对invalidate需要做的是将NSTimer设置为nil，如下所示：

[_timerAnimacao invalidate];
_timerAnimacao = nil;

如果你不这样做，你的下一个命令将无法正常工作，例如：

if(_timerAnimacao)
  [_timerAnimacao invalidate];

请注意：if(_timerAnimacao)与if(_timerAnimacao == nil)相同！

同时看看这个：How do I use NSTimer?

Answer 2

当你启动和无效时，NSTimer的实例需要在内存中。

您可以通过两种方式实现这一目标：

将NSTimer设置为Appdelegate类的属性，并在需要的地方使用它。

NSTimer * timer = [（MyAppDelegate *）[[UIApplication sharedApplication] delegate] .timer;
创建一个新类并将NStimer设置为属性。创建一个类方法以返回该类的单例实例。

static MyClass * obj = NULL;
- （MyClass *）实例 { @synchronized（个体经营） { if（obj == NULL） obj = [[self alloc] init]; }
  
  返回（OBJ）; }

我更喜欢第二种方法。

使NSTimer bas访问无效

2 个答案: