Segue NSTimer 和 Delayed perform

segue 、 NSTimer 和 Delayed perform 的自我学习

UIStoryboardSegue ：NSObject

+ (instancetype)segueWithIdentifier:(nullableNSString*)identifier source:(UIViewController*)source destination:(UIViewController*)destination performHandler:(void(^)(void))performHandler;

- (instancetype)initWithIdentifier:(nullableNSString*)identifier source:(UIViewController*)source destination:(UIViewController*)destination ;

- (instancetype)init;

@property(nullable,nonatomic,copy,readonly)NSString*identifier;//标识符

@property(nonatomic,readonly)__kindofUIViewController *sourceViewController;//源控制器

@property(nonatomic,readonly)__kindofUIViewController *destinationViewController;//目的控制器

一个方法，三个属性

NSTimer : NSObject

+ (NSTimer*)timerWithTimeInterval:(NSTimeInterval)ti invocation:(NSInvocation*)invocation repeats:(BOOL)yesOrNo;
+ (NSTimer*)scheduledTimerWithTimeInterval:(NSTimeInterval)ti invocation:(NSInvocation*)invocation repeats:(BOOL)yesOrNo;

+ (NSTimer*)timerWithTimeInterval:(NSTimeInterval)ti target:(id)aTarget selector:(SEL)aSelector userInfo:(nullableid)userInfo repeats:(BOOL)yesOrNo;
+ (NSTimer*)scheduledTimerWithTimeInterval:(NSTimeInterval)ti target:(id)aTarget selector:(SEL)aSelector userInfo:(nullableid)userInfo repeats:(BOOL)yesOrNo;

- (instancetype)initWithFireDate:(NSDate*)date interval:(NSTimeInterval)ti target:(id)t selector:(SEL)s userInfo:(nullableid)ui repeats:(BOOL)rep;

- (void)fire; 定时器开始

- (void)invalidate;  定时器 结束

@property(copy)NSDate*fireDate;

@property(readonly)NSTimeIntervaltimeInterval;

@propertyNSTimeIntervaltolerance;

@property(readonly,getter=isValid)BOOLvalid;

@property(nullable,readonly,retain)iduserInfo;

scheduledTimerWithTimeInterval:(NSTimeInterval)seconds  

预订一个Timer,设置一个时间间隔。

表示输入一个时间间隔对象，以秒为单位，一个>0的浮点类型的值，如果该值<0,系统会默认为0.1

 target:(id)aTarget

表示发送的对象，如self

 selector:(SEL)aSelector

方法选择器，在时间间隔内，选择调用一个实例方法

userInfo:(id)userInfo

此参数可以为nil，当定时器失效时，由你指定的对象保留和释放该定时器。

repeats:(BOOL)yesOrNo

当YES时，定时器会不断循环直至失效或被释放，当NO时，定时器会循环发送一次就失效。

invocation:(NSInvocation *)invocation

sche

#不用scheduled方式初始化的，需要手动addTimer:forMode: 将timer添加到一个runloop中。

　　而scheduled的初始化方法将以默认mode直接添加到当前的runloop中.

Delayed perform 延迟执行

NSObject (NSDelayedPerforming)

- (void)performSelector:(SEL)aSelector withObject:(nullableid)anArgument afterDelay:(NSTimeInterval)delay inModes:(NSArray<NSString*> *)modes;
- (void)performSelector:(SEL)aSelector withObject:(nullableid)anArgument afterDelay:(NSTimeInterval)delay;  最常用
+ (void)cancelPreviousPerformRequestsWithTarget:(id)aTarget selector:(SEL)aSelector object:(nullableid)anArgument;

+ (void)cancelPreviousPerformRequestsWithTarget:(id)aTarget;

NSRunLoop (NSOrderedPerform)

- (void)performSelector:(SEL)aSelector target:(id)target argument:(nullableid)arg order:(NSUInteger)order modes:(NSArray<NSString*> *)modes;
- (void)cancelPerformSelector:(SEL)aSelector target:(id)target argument:(nullableid)arg;

- (void)cancelPerformSelectorsWithTarget:(id)target;

提示框的弹出和自动取消

if([nameisEqualToString:@""] || [phoneNum isEqualToString:@""] ) {
        UIAlertController *alert = [UIAlertControlleralertControllerWithTitle:@"提示"message:@"姓名或手机号为空"preferredStyle:UIAlertControllerStyleAlert];
        [selfpresentViewController:alertanimated:YEScompletion:nil];

        [selfperformSelector:@selector(dismissViewControllerAnimated:completion:)withObject:nilafterDelay:2.0];