ios - UItableViewCell 上 infoButton 的 UIPopOver

Question

嗨，我正在尝试显示来自 uitablecell 上的信息按钮单击的弹出窗口。但是当我运行它时，模拟器就挂了。以下是我的代码

这是在 cellForRowAtIndexPath

            UIButton *helpButton =  [UIButton buttonWithType:UIButtonTypeInfoDark ] ;
            helpButton.frame = CGRectMake(200, 16, 200 ,15);
            helpButton.tag = 458;
            [helpButton addTarget:self action:@selector(doHelp:) forControlEvents:UIControlEventTouchUpInside];
            [cell.contentView addSubview:helpButton];

我的 doHelp 方法

-(void)doHelp : (id)sender{
  testviewcontroller=[[UIViewController alloc]init];
  popTable = [[UITableView alloc]initWithFrame:CGRectMake(10, 40, 80, 120)  style:UITableViewStyleGrouped];
  popTable.delegate = self;
  popTable.dataSource = self;

  testviewcontroller.view=popTable;


  navController = [[UINavigationController alloc] initWithRootViewController:testviewcontroller];

  pop=[[UIPopoverController alloc]initWithContentViewController:navController];


  // navController.navigationBar.topItem.rightBarButtonItem=searchItem;
  //  navController1.navigationBar.topItem.title=@"Reporting Type";
  navController.navigationBarHidden=true;

  [pop presentPopoverFromRect:[sender frame] inView:self.view permittedArrowDirections:UIPopoverArrowDirectionRight animated:YES];
  [pop setPopoverContentSize:CGSizeMake(250,107)];

 }

任何 hep 将不胜感激。