#import "ViewController.h"
@interface ViewController ()
{
UIButton *_button;
__block int timeout;
}
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
_button = [UIButton buttonWithType:UIButtonTypeCustom];
_button.frame = CGRectMake(0, 0, 100, 30);
_button.center = self.view.center;
[_button setTitle:@"发送验证码" forState:UIControlStateNormal];
[_button setBackgroundColor:[UIColor purpleColor]];
_button.layer.cornerRadius = 5;
_button.clipsToBounds = YES;
[_button addTarget:self action:@selector(verificationCodeCountDown) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:_button];
}
- (void)verificationCodeCountDown
{
__block NSString *strTime = [[NSString alloc] init];
//验证码倒计时
timeout=10; //倒计时时间
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_source_t _timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
dispatch_source_set_timer(_timer,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行
dispatch_source_set_event_handler(_timer, ^{
if(timeout<=0){ //倒计时结束，关闭
dispatch_source_cancel(_timer);
dispatch_async(dispatch_get_main_queue(), ^{
//设置界面的按钮显示 根据自己需求设置
[_button setTitle:@"发送验证码" forState:UIControlStateNormal];
_button.userInteractionEnabled = YES;
});
}else{
int seconds = timeout % 120;
if (seconds == 0) {
strTime = [NSString stringWithFormat:@"%d",timeout];
}
else {
strTime = [NSString stringWithFormat:@"%.2d", seconds];
}
dispatch_async(dispatch_get_main_queue(), ^{
//设置界面的按钮显示 根据自己需求设置
[_button setTitle:[NSString stringWithFormat:@"%@秒",strTime] forState:UIControlStateNormal];
_button.userInteractionEnabled = NO;
NSLog(@"倒计时%@",strTime);
});
timeout--;
}
});
dispatch_resume(_timer);
}