[置顶] IOS 关于取消延迟执行函数的种种。performSelector与cancelPreviousPerformRequestsWithTarget
2015-12-29 17:48
501 查看
[cpp]
view plaincopy
@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:
[cpp]
view plaincopy
[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:
[cpp]
view plaincopy
[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。
view plaincopy
@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:
[cpp]
view plaincopy
[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:
[cpp]
view plaincopy
[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。
相关文章推荐
- UIView添加分类
- 芒果iOS开发之ERROR: Error installing rails: Failed to build gem native extension. /nokogiri/gem_make.out
- Frequent Pattern 挖掘之二(FP Growth算法)
- Ansible关于遍历dict获取value的做法
- 判断两个UIColor的颜色值是否相等
- UIAlertView使用
- Access restriction:The type JPEGCodec is not accessible due to restriction on required library C:\Program Files\Java\jre6\lib\rt.jar
- iOS中UIImage和UIColor之间的转换
- UIPageViewController-浅析
- UI - TableView高级(自定义cell、cell自定义高度)
- for-switch-continue的嵌套使用问题。
- UIScrollView做图片缩放
- IOS学习笔记——iOS组件之UIScrollView详解
- 使用NSURLCache为NSURLRequest设置缓存
- UIPopoverPresentationController 弹出 UIViewController 包裹的 UICollectionView
- UGUI Navigation Events
- 提示框的综合使用--UIAlertViewController
- TableView性能优化——动态cell适应工具(UITableView+FDTemplateLayoutCell)
- IOS:UIPickerView设置三组数据联动的选择框(地区,上课时间段等类型数据的选择)
- UITextField和UITextView隐藏键盘