- @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
最近看到大家對cancelPreviousPerformRequestsWithTarget不能取消帶參數的
- (void)performSelector:(SEL)aSelector withObject:(id)anArgument afterDelay:(NSTimeInterval)delay;
情況,寫了一點點代碼調試了一下,發現如果是帶參數,那取消時的參數也要一致,否則不能取消成功。
開始延遲執行:
- [self performSelector:@selector(didRuninCurrModel:) withObject:[NSNumber numberWithBool:YES] afterDelay:3.0f];
- [self performSelector:@selector(didRuninCurrModelNoArgument) withObject:nil afterDelay:3.0f];
假如在三秒內執行以下取消方法,則結果分別爲:
- [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。參數不匹配
- [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(didRuninCurrModel:) object:nil];//不能取消成功。參數不匹配
- [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。