1.按钮选中不可取消

   btn.layer.borderColor = btn.selected?Color_Theme.CGColor:Color_Btn_Border.CGColor;
    //单选
    if (btn.selected) {
        for (UIButton *btnTemp in self.contentView.subviews) {
            if ([btnTemp isKindOfClass:[UIButton class]] && ![btnTemp isEqual:btn]) {
                    btnTemp.selected = NO;
                    btnTemp.layer.borderColor = Color_Btn_Border.CGColor;
            }
        }
    }
    

2.按钮点击选中，再次点击取消选中

btn.selected = !btn.selected;
 btn.layer.borderColor = btn.selected?Color_Theme.CGColor:Color_Btn_Border.CGColor;
    //单选
    if (btn.selected) {
        for (UIButton *btnTemp in self.contentView.subviews) {
            if ([btnTemp isKindOfClass:[UIButton class]] && ![btnTemp isEqual:btn]) {
                    btnTemp.selected = NO;
                    btnTemp.layer.borderColor = Color_Btn_Border.CGColor;
            }
        }
    }