Objective-C UIDocumentInteractionController加载灰屏

Question

I am trying to preview a UIDocumentInteractionController like so:

NSString* filePath = [[NSBundle mainBundle] pathForResource:@"FLW-0032 Design Sketches" ofType:@"pdf"];

_previewItemURL = [NSURL URLWithString:filePath];

UIDocumentInteractionController *documentInteractionController =[UIDocumentInteractionController interactionControllerWithURL:_previewItemURL];

documentInteractionController.delegate = self;

[documentInteractionController presentPreviewAnimated:YES];

And all I get is the gray screen with the file name. The file is 5.5MB

What am I doing wrong?

Here is my delegate method:

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

I am seeing this in my console log

[Snapshotting] Snapshotting a view (0x108c80800, _UIButtonBarStackView) that has not been rendered at least once requires afterScreenUpdates:YES. 2018-03-07 20:39:16.169613-0500 SchedulingiPadApplication[417:61893] [default] Couldn't issue file extension for url: file:///var/containers/Bundle/Application/23540D89-0841-4F12-A6A4-A2840D4076F4/SchedulingiPadApplication.app/FLW-0032%20Design%20Sketches.pdf

PreviewItem

This happens when I a presenting the documentInteractionController

Answer 1

You need to use NSURL fileURLWithPath: , not URLWithString: .

Better yet, use NSBundle URLForResource:withExtension: to get the NSURL directly.