遍历父视图上的button

 for (UIView * thebtn in [self.view subviews])
 {
     if ([thebtn isKindOfClass:[UIButton class]])
        {     //***改变字体颜色
            [(UIButton *)thebtn setTitleColor:[UIColor redColor]     forState:UIControlStateNormal];
            //***改变背景
         [(UIButton *)thebtn setBackgroundImage:nil forState:UIControlStateNormal];
   }
 }