iOS用SegmentController来切换tableView的时候 reloadData会造成数据重复创建 解决办法

把在Cell上面创建的控件放在Cell==nil的判断里面，这样，每次进来就会先判断有没有，就可以避免数据重复创建，导致视图越盖越厚

if (cell==nil) {

            cell=[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIDD];

            self.inviteLabel=[[UILabel alloc]initWithFrame:CGRectMake(10,5,[UIScreen mainScreen].bounds.size.width-20,120)];

            self.inviteLabel.numberOfLines=0;

            self.inviteLabel.text=cell_info.title;

            self.inviteLabel.textColor=LABEL_TEXTCOLOR;

            int width=100;

            int height=40;

            self.button=[[UIButton alloc]initWithFrame:CGRectMake([UIScreen mainScreen].bounds.size.width/2-width/2,120+10, width, height)];

            self.button.backgroundColor=[UIColor redColor];

            [self.button setBackgroundImage:[UIImage imageNamed:cell_info.cp] forState:UIControlStateNormal];

            NSLog(@"cell_info.cp:%@",cell_info.cp);

            //增加长按手势

            UILongPressGestureRecognizer *longPress=[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longPress:)];

            [self.inviteLabel addGestureRecognizer:longPress];

            longPress.minimumPressDuration=1.0;

            [cell.contentView addSubview:self.button];

            [cell.contentView addSubview:self.inviteLabel];

            cell.backgroundColor=CELL_BACK_COLOR;

        }