Question

单击每一行将引导您进入另一个视图控制器

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
    if( indexPath.row == 0 ){
        titleController     = [[TitleFundraiserController alloc] initWithNibName:@"TitleFundraiserController" bundle:nil];
        [self.navigationController presentViewController:titleController animated:YES completion:nil];
    }
    if( indexPath.row == 1 ) {
        recipientController = [[RecipientController alloc] initWithNibName:@"RecipientController" bundle:nil];
        [self.navigationController presentViewController:recipientController animated:YES completion:nil];
    }
    if( indexPath.row == 2 ) {
        fundController      = [[FundingController alloc] initWithNibName:@"FundingController" bundle:nil];
        [self.navigationController presentViewController:recipientController animated:YES completion:nil];
    }
    if( indexPath.row == 3 ) {
        locationController  = [[LocationController alloc] initWithNibName:@"LocationController" bundle:nil];
        [self.navigationController presentViewController:locationController animated:YES completion:nil];
    }  
}

但是，有时我从控制台收到此错误，我的程序崩溃

  Terminating app due to uncaught exception 'NSInvalidArgumentException', reason:
 'Application tried to present a nil modal view controller on target <UINavigationController: 0x7c7a340>.'

我不知道为什么这么说。

如果您之前遇到此问题，请提供帮助。

由于

Answer 1

我唯一看错的代码是在presentViewController之后，你还需要释放变量：

if ( indexPath.row == 0 ) {
            titleController     =   [[TitleFundraiserController alloc] initWithNibName:@"TitleFundraiserController" bundle:nil];
            [self.navigationController presentViewController:titleController animated:YES completion:nil];
            [titleController release];
    }

我没有看到任何原因导致您随机出现错误，是不是总是在同一行？发生的事情是ViewController没有从笔尖加载，因此返回nil。

Answer 2

当您提交recipientController

时，您在if (indexPath.row == 2)声明中提出了fundController

以下是更正后的代码：

if( indexPath.row == 2 ) {
        fundController = [[FundingController alloc] initWithNibName:@"FundingController" bundle:nil];
        [self.navigationController presentViewController:fundController animated:YES completion:nil];
}

您收到该错误，因为recipientController在此处展示时将为零

在执行presentViewController时获取视图控制器nil

2 个答案: