GCD实现倒计时

男娘i 2022-08-17 14:09 170阅读 0赞

\_\_block int timeout=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(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  
                    \[\_sendCodeBtn setTitle:@"" forState:UIControlStateNormal\];  
                    \[\_sendCodeBtn setBackgroundImage:\[UIImage imageNamed:@"btn\_send\_code"\] forState:UIControlStateNormal\];  
                    \[\_sendCodeBtn setUserInteractionEnabled:YES\];  
                \});  
            \}else\{  
                //            int minutes = timeout / 60;  
                  
                int seconds = timeout % 60;  
                  
                NSString \*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  
                    //                    NSLog(@"\_\_\_\_%@",strTime);  
                    \[\_sendCodeBtn setTitle:\[NSString stringWithFormat:@"%@秒后重新获取",strTime\] forState:UIControlStateNormal\];  
                    \[\_sendCodeBtn setBackgroundImage:\[UIImage imageNamed:@"btn\_send\_code\_disabled"\] forState:UIControlStateNormal\];  
                    \[\_sendCodeBtn setUserInteractionEnabled:NO\];  
                \});  
                timeout--;  
                  
            \}  
        \});  
        dispatch\_resume(\_timer);  
    \}