个人博客: LiCheng的博客
引言:
验证码倒计时按钮的应用是非常普遍的，本文介绍了IOS实现验证码倒计时功能，点击获取验证码，进入时间倒计时，感兴趣的小伙伴们可以参考一下:
效果图
实现思路:
- 创建按钮, 添加点击方法;
- 用NSTimer定时器, 每秒执行一次, 定时改变Button的title,改变Button的样式, 设置Button不可点击;
- 若倒计时结束, 定时器关闭, 并改变Button的样式, 可以点击;
代码如下:
在按钮的点击事件里调用该方法.
// 开启倒计时效果
-(void)openCountdown{
__block NSInteger time = 59; //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(time <= 0){ //倒计时结束，关闭
dispatch_source_cancel(_timer);
dispatch_async(dispatch_get_main_queue(), ^{
//设置按钮的样式
[self.authCodeBtn setTitle:@"重新发送" forState:UIControlStateNormal];
[self.authCodeBtn setTitleColor:[UIColor colorFromHexCode:@"FB8557"] forState:UIControlStateNormal];
self.authCodeBtn.userInteractionEnabled = YES;
});
}else{
int seconds = time % 60;
dispatch_async(dispatch_get_main_queue(), ^{
//设置按钮显示读秒效果
[self.authCodeBtn setTitle:[NSString stringWithFormat:@"重新发送(%.2d)", seconds] forState:UIControlStateNormal];
[self.authCodeBtn setTitleColor:[UIColor colorFromHexCode:@"979797"] forState:UIControlStateNormal];
self.authCodeBtn.userInteractionEnabled = NO;
});
time--;
}
});
dispatch_resume(_timer);
}
注意点:
我们在创建Button时, 要设置Button的样式:
当type为: UIButtonTypeCustom时 , 是读秒的效果.
当type为: 其他时, 是一闪一闪的效果.
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GitHub: https://github.com/LiCheng244/LCUtils
个人博客: http://www.licheng244.com/
