防止按钮连续重复点击

 1 // 按钮方法
 2 - (IBAction)btnClickAfterDelay:(UIButton *)sender {
 3     
 4     NSLog(@"0000000");
 5     
 6     if (sender.selected) return;
 7     
 8     sender.selected = YES;
 9     
10     [self performSelector:@selector(btnAction:) withObject:sender afterDelay:3.0];
11     
12     NSLog(@"9999999");
13     
14 }
15 
16 // 执行的任务
17 - (void)btnAction:(UIButton*)sender{
18     
19     NSLog(@"55555555");
20     sender.selected = NO;
21     
22 }