IOS 关于取消延迟执行函数的种种。performSelector与cancelPreviousPerformRequestsWithTarget

来源:互联网 发布:unity3d 性能测试工具 编辑:程序博客网 时间:2024/05/18 12:42
@interface NSObject (NSDelayedPerforming)    - (void)performSelector:(SEL)aSelector withObject:(id)anArgument afterDelay:(NSTimeInterval)delay inModes:(NSArray *)modes;  - (void)performSelector:(SEL)aSelector withObject:(id)anArgument afterDelay:(NSTimeInterval)delay;  + (void)cancelPreviousPerformRequestsWithTarget:(id)aTarget selector:(SEL)aSelector object:(id)anArgument;  + (void)cancelPreviousPerformRequestsWithTarget:(id)aTarget;    @end  


最近看到大家对cancelPreviousPerformRequestsWithTarget不能取消带参数的
- (void)performSelector:(SEL)aSelector withObject:(id)anArgument afterDelay:(NSTimeInterval)delay;
情况,写了一点点代码调试了一下,发现如果是带参数,那取消时的参数也要一致,否则不能取消成功。
开始延迟执行:


[self performSelector:@selector(didRuninCurrModel:) withObject:[NSNumber numberWithBool:YES] afterDelay:3.0f];    [self performSelector:@selector(didRuninCurrModelNoArgument) withObject:nil afterDelay:3.0f];  


假如在三秒内执行以下取消方法,则结果分别为:


[NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(didRuninCurrModel:) object:[NSNumber numberWithBool:YES]];//可以取消成功。    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(didRuninCurrModel:) object:[NSNumber numberWithBool:NO]];//不能取消成功。参数不匹配    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(didRuninCurrModel:) object:nil];//不能取消成功。参数不匹配    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(didRuninCurrModelNoArgument) object:nil];//可以成功取消    [NSObject cancelPreviousPerformRequestsWithTarget:self];//可以成功取消全部。  [[self class] cancelPreviousPerformRequestsWithTarget:self];//可以成功取消全部。  

代码下载地址:http://download.csdn.net/detail/samuelltk/5481327



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