Question

我正在使用UIDocumentInteractionController来显示PDF。用户从表格视图中选择要显示的PDF。

当我完成查看PDF并单击“完成”按钮后，我的表视图将重新加载并显示。但表格视图显示为冻结，无法向上或向下滚动。所以我的didSelectRowAtIndexPath方法不起作用。

这是我的代码：

NSString *filePath = [NSString stringWithFormat:@"%@/%@", [datasource PDFFilePath], [ffd fileFolderName]];

    NSURL *URL = [NSURL fileURLWithPath:filePath];

    if (URL)
    {
        self.documentInteractionController = [UIDocumentInteractionController interactionControllerWithURL:URL];

        [self.documentInteractionController setDelegate:self];

        [self.documentInteractionController presentPreviewAnimated:YES];
    }

- (UIViewController *) documentInteractionControllerViewControllerForPreview: (UIDocumentInteractionController *) controller {
    return self;
}

- (void)documentInteractionControllerDidEndPreview:(UIDocumentInteractionController *)controller
{
    [_tableView reloadData];
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    FileFolderData *ffd =
    [[datasource.finalData valueForKey:
      [[[datasource.finalData allKeys] sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)] objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];

    if ([ffd isFile])
    {
        [_tableView setUserInteractionEnabled:NO];
    }

    [self performSelector:@selector(SwitchFolders:) withObject:indexPath afterDelay:0.1f];
}

我的问题是，如何在查看PDF后再次使用UITableView？

我收到此错误

Assigning to 'id<UITableViewDataSource> _Nullable' from incompatible type 'ViewController *const __strong

在这一行：

_tableView.dataSource = self;

但这可能是不相关的

其他代码：

- (void)SwitchFolders:(NSIndexPath *)indexPath
{
    FileFolderData *ffd =
    [[datasource.finalData valueForKey:
      [[[datasource.finalData allKeys] sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)] objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];

    if([ffd isFolder])
    {
        [datasource GetFilesAndFolders:[ffd fileFolderName] :NO];
        [_tableView reloadData];
        [_tableView reloadSections:[NSIndexSet indexSetWithIndex:0] withRowAnimation:UITableViewRowAnimationTop];
    }
    else if ([ffd isFile])
    {
        [self performSelectorInBackground:@selector(DownloadPDF:) withObject:ffd];
    }


}

在选择单元格时调用此方法。使用UIDocumentInteractionController后再次选择单元格不起作用。

更多代码

- (void)PDFDownloadSuccess:(FileFolderData *)ffd
{
    NSString *filePath = [NSString stringWithFormat:@"%@/%@", [datasource PDFFilePath], [ffd fileFolderName]];

    NSURL *URL = [NSURL fileURLWithPath:filePath];

    if (URL)
    {
        self.documentInteractionController = [UIDocumentInteractionController interactionControllerWithURL:URL];

        [self.documentInteractionController setDelegate:self];

        [self.documentInteractionController presentPreviewAnimated:YES];
    }

}

这就是调用PDFSuccessDownload的方式：

- (void)DownloadPDF:(FileFolderData *)ffd
{

    if([datasource PDFDownload_ASynch:[ffd fileFolderName]])
    {
        [self performSelectorOnMainThread:@selector(PDFDownloadSuccess:) withObject:ffd waitUntilDone:YES];
    }
    else
    {
        [self performSelectorOnMainThread:@selector(PDFDownloadFail:) withObject:ffd waitUntilDone:YES];
    }

}

SwitchFolders方法正在调用DownloadPDF，当你选择一个单元格时会调用它。

Answer 1

通过执行以下操作解决了此问题：

- (void)documentInteractionControllerDidEndPreview:(UIDocumentInteractionController *)controller
{
    [_tableView setUserInteractionEnabled:YES];
}

在PDF关闭后将UITableView的用户交互设置为“是”。

Objective-C didSelectRowAtIndexPath无法使用UIDocumentInteractionController

1 个答案: