#uidocumentinteractioncontroller

Quick Look Preview Controller in Swift

Did you know that Apple, through iOS technologies like the UIDocumentInteractionController class and the Quick Look framework, allows iOS developers to provide previews of all types of files even if their iOS app doesn’t directly support those files? Yes, with iOS, if you simply need to provide a preview of a document within your app, you can easily use the Quick Look framework.

The easy way to use the "open with" menu (like a Popover in iPad, like a ActionSheet otherwise) is using the UIDocumentInteractionController

"A document interaction controller (available from iOS 3.2) along with a delegate object, provides in-app support for managing user interactions with files in the local system. For example, an email program might use this class to allow the user to preview attachments and open them in other apps. Use this class to present an appropriate user interface for previewing, opening, copying, or printing a specified file."

Well, add the UIDocumentInteractionControllerDelegate protocol into the .h file.

In the .m use the code below and keep your fingers crossed :)

- (void)onOpenWith:(UIButton *)theButton path:(NSString *)path { NSURL *URL = [NSURL fileURLWithPath:path]; if (URL) { self.documentInteractionController = [UIDocumentInteractionController interactionControllerWithURL:URL]; self.documentInteractionController.delegate = self; //self.documentInteractionController.name = @"Title"; //self.documentInteractionController.UTI = @"com.adobe.pdf"; [self.documentInteractionController presentOptionsMenuFromRect:CGRectZero inView:theButton animated:YES]; } } #pragma mark - UIDocumentInteractionControllerDelegate - (UIViewController *)documentInteractionControllerViewControllerForPreview:(UIDocumentInteractionController *)controller { return self; } - (UIView *)documentInteractionControllerViewForPreview:(UIDocumentInteractionController *)controller { return self.view; } - (CGRect)documentInteractionControllerRectForPreview:(UIDocumentInteractionController *)controller { return self.view.frame; }

For as simple as opening PDF's in iBooks for iPhone and iPad I had some issues.  Here is a short guide to do just that, open PDF's from your application into iBooks.  This demo will be using the iPhone, although I don't think there will be much difference on iPhone or iPad.

First of all we will be using the UIKit Framework, this is generally already included into all headers you create. We will be using the UIDocumentInteractionController Class

UIDocumentInteractionController Documentation

First of all you will need to create a NSURL object like so:

NSURL *url = [NSURL fileURLWithPath:@"Some File URL"];

Next is what took me a while to figure out, the fact that the UIDocumentInteractionController object is autoreleased object.  Thus once you leave the code block you create it in, it will be released and crash your application.

So to get around this I use the object as a property, and release it from memory at a later point.

docController = [UIDocumentInteractionController interactionControllerWithURL:url];

docController.delegate = self;

[docController retain];

BOOL isValid = [docController presentOpenInMenuFromRect:CGRectZero inView:self.view animated:YES];

Using the presentOpenInMenuFromRect will return whether there is a valid application that can open the file.  If there isn't it will return False.  In this case a PDF can be opened by iBooks, I add some extra validation to display an error message to the user if the file cannot be opened as expected.  

In short this code listed will open an UIActionSheet with the iBooks selection, but if the file is not valid nothing will happen.

The following delegate methods will need to be implemented:

- (void)documentInteractionController:(UIDocumentInteractionController *)controller willBeginSendingToApplication:(NSString *)application

- (void)documentInteractionController:(UIDocumentInteractionController *)controller didEndSendingToApplication:(NSString *)application

- (void)documentInteractionControllerDidDismissOpenInMenu:(UIDocumentInteractionController *)controller