- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    //重用标识符
    static NSString * identifider = @"reuse";
    //去重用队列中根据标识符取可重用的cell
  AddressBookCell * cell =  [tableView dequeueReusableCellWithIdentifier:identifider];
    
    if (!cell) {
        cell = [[[AddressBookCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifider] autorelease];
        cell.delegate = self;
    }
    cell.indexPath = indexPath;
    //先获取key
    //key 对应的数组
    //数组中获取元素对象
    cell.nameLabel.text =   ((AddressPerson *)(self.addressBook[   self.orderedKeys[indexPath.section]][indexPath.row])).name;
    cell.phoneNumber.text = ((AddressPerson *)(self.addressBook[   self.orderedKeys[indexPath.section]][indexPath.row])).phoneNumber;
    cell.photoView.image = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForAuxiliaryExecutable:((AddressPerson *)(self.addressBook[   self.orderedKeys[indexPath.section]][indexPath.row])).imageName]];
    return cell;
    
}


//重用机制
    
    //1. 创建重用标识符 ,
  static   NSString * identifier = @"lanouhn";
    
    //2. 去重用队列取出可重用的cell
    
   StudentCell * cell =  [tableView dequeueReusableCellWithIdentifier:identifier];
    
    //3. 判断是否成功取到可重用的cell  .
    
    if (!cell) {
        //如果没有成功取到可重用的cell ,就创建一个cell
        //创建cell之后一定要给cell贴一个重用标识符 , 方便别人重用
        cell = [[[StudentCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:identifier] autorelease];
        
     //   NSLog(@"%d",_num ++);
    }
    
    //cell.textLabel.text = @"ffff";
   // cell.detailTextLabel.text = @"dddd";
    cell.la.text = @"gagaga";
    return  cell;