首页 / 移动开发 / IOS / IOS实现验证码倒计时功能（二）

具体代码：

定义一个发送验证码的按钮，添加点击事件

 //发送验证码按钮_sentCodeBtn = [[UIButton alloc] initWithFrame:CGRectMake（kScreenWidth - 27 - 4 - 94, CGRectGetMinY（_registerCodeFD.frame） + 4, 94, 40）];[_sentCodeBtn setBackgroundColor:colorWithRGBA（0, 191, 191, 0.9）];[_sentCodeBtn setTitle:@"发送验证码" forState:UIControlStateNormal];[_sentCodeBtn.titleLabel setFont:[UIFont systemFontOfSize:13.0f]];//设置圆角[_sentCodeBtn.layer setCornerRadius:3.0f];[_sentCodeBtn.layer setShouldRasterize:YES];[_sentCodeBtn.layer setRasterizationScale:[UIScreen mainScreen].scale];//发送事件[_sentCodeBtn addTarget:self action:@selector（sentCodeMethod） forControlEvents:UIControlEventTouchUpInside];[self.view addSubview:_sentCodeBtn];

监听事件：

//发送验证码-（void）sentCodeMethod{ NSLog（@"发送验证码。。"）; //计时器发送验证码 [self sentPhoneCodeTimeMethod]; //调用发送验证码接口-》}//计时器发送验证码-（void）sentPhoneCodeTimeMethod{ //倒计时时间 - 60秒 __block NSInteger timeOut = 59; //执行队列 dispatch_queue_t queue = dispatch_get_global_queue（DISPATCH_QUEUE_PRIORITY_DEFAULT, 0）; //计时器 -》dispatch_source_set_timer自动生成 dispatch_source_t timer = dispatch_source_create（DISPATCH_SOURCE_TYPE_TIMER, 0, 0, queue）; dispatch_source_set_timer（timer, DISPATCH_TIME_NOW, 1.0 * NSEC_PER_SEC, 0 * NSEC_PER_SEC）; dispatch_source_set_event_handler（timer, ^{if （timeOut <= 0） { dispatch_source_cancel（timer）; //主线程设置按钮样式-》 dispatch_async（dispatch_get_main_queue（）, ^{[_sentCodeBtn setTitle:@"发送验证码" forState:UIControlStateNormal];[_sentCodeBtn setUserInteractionEnabled:YES]; }）;}else{ //开始计时 //剩余秒数 seconds NSInteger seconds = timeOut % 60; NSString *strTime = [NSString stringWithFormat:@"%.1ld",seconds]; //主线程设置按钮样式 dispatch_async（dispatch_get_main_queue（）, ^{[UIView beginAnimations:nil context:nil];[UIView setAnimationDuration:1.0];[_sentCodeBtn setTitle:[NSString stringWithFormat:@"%@S后重新发送",strTime] forState:UIControlStateNormal];[UIView commitAnimations];//计时器件不允许点击[_sentCodeBtn setUserInteractionEnabled:NO]; }）; timeOut--;} }）; dispatch_resume（timer）;}