ios 通知监听App进入后台，然后再进入App（获取验证码的时间间隔）

1.自定义按钮继承与UIButton

@interface SMSButton ()

{

int _timerNumber; //定时器时间

long long int _backGroundInterval;//时间戳

}

@property (nonatomic, strong) NSTimer *smsTime;

@property (nonatomic, strong) UIActivityIndicatorView *indicatorView;

@end

@implementation SMSButton

2.初始化方法

-(id)initWithCoder:(NSCoder *)aDecoder

{

self = [super initWithCoder:aDecoder];

if (self) {

self.indicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];

[self addSubview:self.indicatorView];

self.indicatorView.center = CGPointMake(self.width/2, self.height/2);

self.indicatorView.hidden = YES;

[self addObserver];

}

return self;

}

3.掉接口获取验证码

- (void)startWithPhoneNumber:(NSString *)phoneNumber

{

[self startIndicator];

NSMutableDictionary *parametersDic = [NSMutableDictionary dictionary];

[parametersDic setObject_package:phoneNumber forKey:@"telephone" performMethodInfo:MDIC_PERFORMMETHODINFO];

[PHHTTPManager postPath:MobileSend paraDict:parametersDic success:^(NSString *respMsg, NSString *respCode, NSDictionary *responseObject) {

[self stopIndicator];

[self startTimer];

ALERTSHOW(@"验证码已发送");

} failure:^(NSString *errorMsg, NSUInteger errorCode) {

[self stopIndicator];

[self resetState];

}];

4.设置网络请求的加载提示和设置定时器

-(void)startIndicator

{

[self setupTitle:@""];

self.indicatorView.hidden = NO;

[self.indicatorView startAnimating];

self.userInteractionEnabled = NO;

}

-(void)stopIndicator

{

[self.indicatorView stopAnimating];

self.indicatorView.hidden = YES;

}

-(void)startTimer

{

_timerNumber = 120;

self.smsTime = [NSTimer scheduledTimerWithTimeInterval:1.0f target:self selector:@selector(handleNumberTimer:) userInfo:nil repeats:YES];

}

- (void)handleNumberTimer:(id)sender

{

_timerNumber--;

if (_timerNumber > 0) {

[self handleNumberTimerRunning];

}else{

[self handleNumberTimerStop];

}

}

- (void)handleNumberTimerRunning

{

[self setupTitle:[NSString stringWithFormat:@"%d秒",_timerNumber]];

}

- (void)handleNumberTimerStop

{

[self resetState];

}

- (void)resetState

{

[_smsTime invalidate];

_smsTime = nil;

self.userInteractionEnabled = YES;

[self setupTitle:@"获取验证码"];

}

- (void)setupTitle:(NSString *)titleStr

{

[self setTitle:titleStr forState:UIControlStateNormal];

}

5.注册监听者

//监听通知

-(void)addObserver

{

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handleAppDidBackGround) name:UIApplicationDidEnterBackgroundNotification object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handleAppDidEnterForeground) name:UIApplicationWillEnterForegroundNotification object:nil];

}

//程序进入后台

-(void)handleAppDidBackGround

{

_backGroundInterval = (long long int)[[NSDate date] timeIntervalSince1970];//取当前时间戳

}

//程序进入前台

-(void)handleAppDidEnterForeground

{

long long int foreInterval = (long long int)[[NSDate date] timeIntervalSince1970];//取当前时间戳

int differ = (int)( foreInterval - _backGroundInterval);

_timerNumber = (_timerNumber >= 0)?(_timerNumber - differ):_timerNumber;

}

6.移除监听者

//移除通知

-(void)removeObserver

{

[[NSNotificationCenter defaultCenter] removeObserver:self];

}

-(void)dealloc

{

[self removeObserver];

}