didSelectRowAtIndexPath 中的详细信息项显示为 null
现在我有一个表格，其中列出了许多 PDF。用户可以从表中选择 PDF，它将显示在视图中。现在，当我从表中选择项目时，它应该将 detailView 的详细项目更改为我选择的行中的项目，此外还将变量 i 更改为所选的行号。
这是我的 DidSelectRowAtIndexPath 方法的样子：
- (void)tableView:(UITableView *)aTableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
affirmaPDFViewController.detailItem = [NSString stringWithFormat:@"%@", [listOfPDF objectAtIndex:indexPath.row]];
affirmaPDFViewController.i = indexPath.row;
NSLog(@"%d", indexPath.row); //returns the proper value
NSLog(@"%@", [listOfPDF objectAtIndex:indexPath.row]); //returns the proper value
//NSLog(@"%d", affirmaPDFViewController.i); //DOES NOT return the proper value
//NSLog(@"%@", affirmaPDFViewController.detailItem); //DOES NOT return the proper value
}
对于前两个 NSLog，它们显示正确的信息，但是当我检查最后两个时，它们会显示 affirmaPDFViewController.i = 0 且 affirmaPDFViewController.detailItem = null。当我需要 affirmaPDFViewController.i= indexPath.row 和 affirmaPDFViewController.detailItem = 我选择的行中的项目时。
有人知道为什么他们没有提出正确的价值观吗？
提前致谢！
Right now I have a table with a number of PDFs listed. From the table the user can select a PDF and it will be displayed in the view. Right now when I select and item from the table it should change the detailView's detailItem to the item in the row I selected, in addition change the variable i to the selected row number.
Here is what my DidSelectRowAtIndexPath method looks like:
- (void)tableView:(UITableView *)aTableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
affirmaPDFViewController.detailItem = [NSString stringWithFormat:@"%@", [listOfPDF objectAtIndex:indexPath.row]];
affirmaPDFViewController.i = indexPath.row;
NSLog(@"%d", indexPath.row); //returns the proper value
NSLog(@"%@", [listOfPDF objectAtIndex:indexPath.row]); //returns the proper value
//NSLog(@"%d", affirmaPDFViewController.i); //DOES NOT return the proper value
//NSLog(@"%@", affirmaPDFViewController.detailItem); //DOES NOT return the proper value
}
for the first two NSLog's, they display the proper information, however when i check the last two they come out with affirmaPDFViewController.i = 0 and affirmaPDFViewController.detailItem = null. When i need the affirmaPDFViewController.i= indexPath.row, and affirmaPDFViewController.detailItem = the item in the row I selected.
Anyone know why they aren't coming out with the proper values?
Thanks in advance!
如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱，如果其他用户或者作者回复了您的评论，将不能在第一时间通知您！
发布评论
评论（1）
您的
affirmaPDFViewController实例为零。检查创建它的方法，并记住您可以在调试器中设置断点来查看它是否是有效的对象。Your instance of
affirmaPDFViewControlleris nil. Check the method where it's created, and remember you can set a breakpoint in the debugger to see if it's a valid object or not.